update querystring – My Programming Notes

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C# || How To Get, Add, Update & Remove Values From A URL Query String Using C#

May 10, 2021 admin No comments

The following is a module with functions which demonstrates how to get, add, update and remove parameters from a query string using C#.

The following functions use System.Web to modify the url.

To use the functions in this module, make sure you have a reference to ‘System.Web‘ in your project.

One way to do this is, in your Solution Explorer (where all the files are shown with your project), right click the ‘References‘ folder, click ‘Add Reference‘, then type ‘System.Web‘ in the search box, and add the reference titled System.Web in the results Tab.

Note: Don’t forget to include the ‘Utils Namespace‘ before running the examples!

1. Add – Single Parameter

The example below demonstrates the use of ‘Utils.HttpParams.Add‘ to add a query string parameter to a url.





		
		
			1. Add - Single Parameter
			
C#
			
			// Add - Single Parameter

// Declare url
var url = "http://programmingnotes.org/";

// Add single key value parameter to the url
var result = Utils.HttpParams.Add(url, new KeyValuePair<string, string>("ids", "1987"));

// Display result
Console.WriteLine(result);

// expected output:
/* 
    http://programmingnotes.org/?ids=1987
*/
			
				
					
				
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						// Add - Single Parameter
 
// Declare url
var url = "http://programmingnotes.org/";
 
// Add single key value parameter to the url
var result = Utils.HttpParams.Add(url, new KeyValuePair<string, string>("ids", "1987"));
 
// Display result
Console.WriteLine(result);
 
// expected output:
/* 
    http://programmingnotes.org/?ids=1987
*/

2. Add – Multiple Parameters

The example below demonstrates the use of ‘Utils.HttpParams.Add‘ to add a query string parameter to a url.





		
		
			2. Add - Multiple Parameters
			
C#
			
			// Add - Multiple Parameters

// Declare url
var url = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer";

// Add multiple key value parameters to the url
var addition = new System.Collections.Specialized.NameValueCollection() {
    {"ids", "2010"},
    {"ids", "2019"},
    {"names", "Lynn"},
    {"names", "Sole"}
};

// Update the url
var result = Utils.HttpParams.Add(url, addition);

// Display result
Console.WriteLine(result);

// expected output:
/*
    http://programmingnotes.org/?ids=1987%2c1991%2c2010%2c2019&names=Kenneth%2cJennifer%2cLynn%2cSole
*/
			
				
					
				
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						// Add - Multiple Parameters
 
// Declare url
var url = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer";
 
// Add multiple key value parameters to the url
var addition = new System.Collections.Specialized.NameValueCollection() {
    {"ids", "2010"},
    {"ids", "2019"},
    {"names", "Lynn"},
    {"names", "Sole"}
};
 
// Update the url
var result = Utils.HttpParams.Add(url, addition);
 
// Display result
Console.WriteLine(result);
 
// expected output:
/*
    http://programmingnotes.org/?ids=1987%2c1991%2c2010%2c2019&names=Kenneth%2cJennifer%2cLynn%2cSole
*/

3. Update – Single Parameter

The example below demonstrates the use of ‘Utils.HttpParams.Update‘ to update a query string parameter to a url.





		
		
			3. Update - Single Parameter
			
C#
			
			// Update - Single Parameter

// Declare url
var url = "http://programmingnotes.org/?ids=1987";

// Update single key value parameter to the url
var result = Utils.HttpParams.Update(url, new KeyValuePair<string, string>("ids", "1991"));

// Display result
Console.WriteLine(result);

// expected output:
/* 
    http://programmingnotes.org/?ids=1991
*/
			
				
					
				
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						// Update - Single Parameter
 
// Declare url
var url = "http://programmingnotes.org/?ids=1987";
 
// Update single key value parameter to the url
var result = Utils.HttpParams.Update(url, new KeyValuePair<string, string>("ids", "1991"));
 
// Display result
Console.WriteLine(result);
 
// expected output:
/* 
    http://programmingnotes.org/?ids=1991
*/

4. Update – Multiple Parameters

The example below demonstrates the use of ‘Utils.HttpParams.Update‘ to update a query string parameter to a url.





		
		
			4. Update - Multiple Parameters
			
C#
			
			// Update - Multiple Parameters

// Declare url
var url = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer";

// Update multiple key value parameters to the url
var addition = new System.Collections.Specialized.NameValueCollection() {
    {"ids", "2010"},
    {"ids", "2019"},
    {"names", "Lynn"},
    {"names", "Sole"}
};

// Update the url
var result = Utils.HttpParams.Update(url, addition);

// Display result
Console.WriteLine(result);

// expected output:
/*
    http://programmingnotes.org/?ids=2010%2c2019&names=Lynn%2cSole
*/
			
				
					
				
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						// Update - Multiple Parameters
 
// Declare url
var url = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer";
 
// Update multiple key value parameters to the url
var addition = new System.Collections.Specialized.NameValueCollection() {
    {"ids", "2010"},
    {"ids", "2019"},
    {"names", "Lynn"},
    {"names", "Sole"}
};
 
// Update the url
var result = Utils.HttpParams.Update(url, addition);
 
// Display result
Console.WriteLine(result);
 
// expected output:
/*
    http://programmingnotes.org/?ids=2010%2c2019&names=Lynn%2cSole
*/

5. Remove – Single Parameter

The example below demonstrates the use of ‘Utils.HttpParams.Remove‘ to remove a query string parameter from a url.





		
		
			5. Remove - Single Parameter
			
C#
			
			// Remove - Single Parameter

// Declare url
var url = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer";

// Remove single parameter from the url
var result = Utils.HttpParams.Remove(url, "names");

// Display result
Console.WriteLine(result);

// expected output:
/*
    http://programmingnotes.org/?ids=1987%2c1991
*/
			
				
					
				
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						// Remove - Single Parameter
 
// Declare url
var url = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer";
 
// Remove single parameter from the url
var result = Utils.HttpParams.Remove(url, "names");
 
// Display result
Console.WriteLine(result);
 
// expected output:
/*
    http://programmingnotes.org/?ids=1987%2c1991
*/

6. Remove – Multiple Parameters

The example below demonstrates the use of ‘Utils.HttpParams.Remove‘ to remove multiple query string parameters from a url.





		
		
			6. Remove - Multiple Parameters
			
C#
			
			// Remove - Multiple Parameters

// Declare url
var url = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer";

// Remove multiple parameters from the url
var result = Utils.HttpParams.Remove(url, new string[] { "ids", "names" });

// Display result
Console.WriteLine(result);

// expected output:
/*
    http://programmingnotes.org/
*/
			
				
					
				
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						// Remove - Multiple Parameters
 
// Declare url
var url = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer";
 
// Remove multiple parameters from the url
var result = Utils.HttpParams.Remove(url, new string[] { "ids", "names" });
 
// Display result
Console.WriteLine(result);
 
// expected output:
/*
    http://programmingnotes.org/
*/

7. Clear – Remove All Parameters

The example below demonstrates the use of ‘Utils.HttpParams.Clear‘ to remove all query string parameters from a url.





		
		
			7. Clear - Remove All Parameters
			
C#
			
			// Clear - Remove All Parameters

// Declare url
var url = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer";

// Remove multiple parameters from the url
var result = Utils.HttpParams.Clear(url);

// Display result
Console.WriteLine(result);

// expected output:
/*
    http://programmingnotes.org/
*/
			
				
					
				
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						// Clear - Remove All Parameters
 
// Declare url
var url = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer";
 
// Remove multiple parameters from the url
var result = Utils.HttpParams.Clear(url);
 
// Display result
Console.WriteLine(result);
 
// expected output:
/*
    http://programmingnotes.org/
*/

8. Get – Get All Parameters

The example below demonstrates the use of ‘Utils.HttpParams.Get‘ to get all query string parameters from a url.





		
		
			8. Get - Get All Parameters
			
C#
			
			// Get - Get All Parameters

// Declare url
var url = "http://programmingnotes.org/?ids=1987,1991,2010,2019&names=Kenneth,Jennifer,Lynn,Sole";

// Get parameters from the url
var result = Utils.HttpParams.Get(url);

// Display result
foreach (string key in result) { 
    Console.WriteLine($"Parameter: {key}, Value: {result[key]}");
}

// expected output:
/*
    Parameter: ids, Value: 1987,1991,2010,2019
    Parameter: names, Value: Kenneth,Jennifer,Lynn,Sole
*/
			
				
					
				
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						// Get - Get All Parameters
 
// Declare url
var url = "http://programmingnotes.org/?ids=1987,1991,2010,2019&names=Kenneth,Jennifer,Lynn,Sole";
 
// Get parameters from the url
var result = Utils.HttpParams.Get(url);
 
// Display result
foreach (string key in result) { 
    Console.WriteLine($"Parameter: {key}, Value: {result[key]}");
}
 
// expected output:
/*
    Parameter: ids, Value: 1987,1991,2010,2019
    Parameter: names, Value: Kenneth,Jennifer,Lynn,Sole
*/

9. Utils Namespace

The following is the Utils Namespace. Include this in your project to start using!





		
		
			Utils Namespace
			
C#
			
			// ============================================================================
//    Author: Kenneth Perkins
//    Date:   May 10, 2021
//    Taken From: http://programmingnotes.org/
//    File:  Utils.cs
//    Description: Handles general utility functions
// ============================================================================
using System;
using System.Collections.Generic;
using System.Linq;

namespace Utils {
    public static class HttpParams {
        /// <summary>
        /// Adds the query string parameters to a url
        /// </summary>
        /// <param name="url">The url to append parameters</param> 
        /// <param name="query">The parameters to add to the url</param> 
        /// <returns>The url appended with the specified query</returns>
        public static string Add(string url, System.Collections.Specialized.NameValueCollection query) {
            return UpdateQuery(url, queryString => {
                var merged = new System.Collections.Specialized.NameValueCollection {
                    queryString,
                    query
                };
                CopyProps(merged, queryString);
            });
        }

        /// <summary>
        /// Adds the query string parameters to a url
        /// </summary>
        /// <param name="url">The url to append parameters</param> 
        /// <param name="param">The parameters to add to the url</param> 
        /// <returns>The url appended with the specified query</returns>
        public static string Add(string url, KeyValuePair<string, string> param)  {
            return Add(url, new System.Collections.Specialized.NameValueCollection() { 
                { param.Key, param.Value } 
            });
        }

        /// <summary>
        /// Updates the query string parameters to a url
        /// </summary>
        /// <param name="url">The url to update parameters</param> 
        /// <param name="query">The parameters to update to the url</param> 
        /// <returns>The url updated with the specified query</returns>
        public static string Update(string url, System.Collections.Specialized.NameValueCollection query) {
            return UpdateQuery(url, queryString => {
                CopyProps(query, queryString);
            });
        }

        /// <summary>
        /// Updates the query string parameters to a url
        /// </summary>
        /// <param name="url">The url to update parameters</param> 
        /// <param name="param">The parameters to update to the url</param> 
        /// <returns>The url updated with the specified query</returns>
        public static string Update(string url, KeyValuePair<string, string> param)  {
            return Update(url, new System.Collections.Specialized.NameValueCollection() { 
                { param.Key, param.Value } 
            });
        }

        /// <summary>
        /// Removes the parameters with the matching keys from the query string of a url
        /// </summary>
        /// <param name="url">The url to remove parameters</param> 
        /// <param name="keys">The parameter keys to remove from the url</param> 
        /// <returns>The url with the parameters removed</returns>
        public static string Remove(string url, IEnumerable<string> keys) {
            return UpdateQuery(url, queryString => {
                foreach (var key in keys) {
                    if (queryString.AllKeys.Contains(key)) { 
                        queryString.Remove(key);
                    }
                }
            });
        }

        /// <summary>
        /// Removes the parameter with the matching key from the query string of a url
        /// </summary>
        /// <param name="url">The url to remove a parameter</param> 
        /// <param name="key">The parameter key to remove from the url</param> 
        /// <returns>The url with the parameter removed</returns>
        public static string Remove(string url, string key) {
            return Remove(url, new string[]{ key });
        }

        /// <summary>
        /// Removes all parameters from the query string of a url
        /// </summary>
        /// <param name="url">The url to clear parameters</param>  
        /// <returns>The url with the parameters removed</returns>
        public static string Clear(string url) {
            return UpdateQuery(url, queryString => {
                queryString.Clear();
            });
        }

        /// <summary>
        /// Returns all parameters from the query string of a url
        /// </summary>
        /// <param name="url">The url to get parameters</param>  
        /// <returns>The url parameters</returns>
        public static System.Collections.Specialized.NameValueCollection Get(string url) {
            System.Collections.Specialized.NameValueCollection result = null;
            UpdateQuery(url, queryString => {
                result = queryString;
            });
            return result;
        }

        /// <summary>
        /// Sets the query string parameters to a url
        /// </summary>
        /// <param name="url">The url to set parameters</param> 
        /// <param name="query">The parameters to set to the url</param> 
        /// <returns>The url set with the specified query</returns>
        public static string Set(string url, System.Collections.Specialized.NameValueCollection query) {
            url = Clear(url);
            return Add(url, query);
        }

        /// <summary>
        /// Sets the query string parameters to a url
        /// </summary>
        /// <param name="url">The url to set parameters</param> 
        /// <param name="param">The parameters to set to the url</param> 
        /// <returns>The url set with the specified query</returns>
        public static string Set(string url, KeyValuePair<string, string> param)  {
            return Set(url, new System.Collections.Specialized.NameValueCollection() { 
                { param.Key, param.Value } 
            });
        }

        private static void CopyProps(System.Collections.Specialized.NameValueCollection source, System.Collections.Specialized.NameValueCollection destination) { 
            foreach (string key in source) {
                destination[key] = source[key];
            }        
        }

        private static string UpdateQuery(string url, Action<System.Collections.Specialized.NameValueCollection> modifyQuery) {
            var uriBuilder = new System.UriBuilder(url);
            var query = System.Web.HttpUtility.ParseQueryString(uriBuilder.Query);
            modifyQuery(query);
            uriBuilder.Query = query.ToString();
            return uriBuilder.Uri.ToString();
        }
    }
}// http://programmingnotes.org/
			
				
					
				
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						// ============================================================================
//    Author: Kenneth Perkins
//    Date:   May 10, 2021
//    Taken From: http://programmingnotes.org/
//    File:  Utils.cs
//    Description: Handles general utility functions
// ============================================================================
using System;
using System.Collections.Generic;
using System.Linq;
 
namespace Utils {
    public static class HttpParams {
        /// <summary>
        /// Adds the query string parameters to a url
        /// </summary>
        /// <param name="url">The url to append parameters</param> 
        /// <param name="query">The parameters to add to the url</param> 
        /// <returns>The url appended with the specified query</returns>
        public static string Add(string url, System.Collections.Specialized.NameValueCollection query) {
            return UpdateQuery(url, queryString => {
                var merged = new System.Collections.Specialized.NameValueCollection {
                    queryString,
                    query
                };
                CopyProps(merged, queryString);
            });
        }
 
        /// <summary>
        /// Adds the query string parameters to a url
        /// </summary>
        /// <param name="url">The url to append parameters</param> 
        /// <param name="param">The parameters to add to the url</param> 
        /// <returns>The url appended with the specified query</returns>
        public static string Add(string url, KeyValuePair<string, string> param)  {
            return Add(url, new System.Collections.Specialized.NameValueCollection() { 
                { param.Key, param.Value } 
            });
        }
 
        /// <summary>
        /// Updates the query string parameters to a url
        /// </summary>
        /// <param name="url">The url to update parameters</param> 
        /// <param name="query">The parameters to update to the url</param> 
        /// <returns>The url updated with the specified query</returns>
        public static string Update(string url, System.Collections.Specialized.NameValueCollection query) {
            return UpdateQuery(url, queryString => {
                CopyProps(query, queryString);
            });
        }
 
        /// <summary>
        /// Updates the query string parameters to a url
        /// </summary>
        /// <param name="url">The url to update parameters</param> 
        /// <param name="param">The parameters to update to the url</param> 
        /// <returns>The url updated with the specified query</returns>
        public static string Update(string url, KeyValuePair<string, string> param)  {
            return Update(url, new System.Collections.Specialized.NameValueCollection() { 
                { param.Key, param.Value } 
            });
        }
 
        /// <summary>
        /// Removes the parameters with the matching keys from the query string of a url
        /// </summary>
        /// <param name="url">The url to remove parameters</param> 
        /// <param name="keys">The parameter keys to remove from the url</param> 
        /// <returns>The url with the parameters removed</returns>
        public static string Remove(string url, IEnumerable<string> keys) {
            return UpdateQuery(url, queryString => {
                foreach (var key in keys) {
                    if (queryString.AllKeys.Contains(key)) { 
                        queryString.Remove(key);
                    }
                }
            });
        }
 
        /// <summary>
        /// Removes the parameter with the matching key from the query string of a url
        /// </summary>
        /// <param name="url">The url to remove a parameter</param> 
        /// <param name="key">The parameter key to remove from the url</param> 
        /// <returns>The url with the parameter removed</returns>
        public static string Remove(string url, string key) {
            return Remove(url, new string[]{ key });
        }
 
        /// <summary>
        /// Removes all parameters from the query string of a url
        /// </summary>
        /// <param name="url">The url to clear parameters</param>  
        /// <returns>The url with the parameters removed</returns>
        public static string Clear(string url) {
            return UpdateQuery(url, queryString => {
                queryString.Clear();
            });
        }
 
        /// <summary>
        /// Returns all parameters from the query string of a url
        /// </summary>
        /// <param name="url">The url to get parameters</param>  
        /// <returns>The url parameters</returns>
        public static System.Collections.Specialized.NameValueCollection Get(string url) {
            System.Collections.Specialized.NameValueCollection result = null;
            UpdateQuery(url, queryString => {
                result = queryString;
            });
            return result;
        }
 
        /// <summary>
        /// Sets the query string parameters to a url
        /// </summary>
        /// <param name="url">The url to set parameters</param> 
        /// <param name="query">The parameters to set to the url</param> 
        /// <returns>The url set with the specified query</returns>
        public static string Set(string url, System.Collections.Specialized.NameValueCollection query) {
            url = Clear(url);
            return Add(url, query);
        }
 
        /// <summary>
        /// Sets the query string parameters to a url
        /// </summary>
        /// <param name="url">The url to set parameters</param> 
        /// <param name="param">The parameters to set to the url</param> 
        /// <returns>The url set with the specified query</returns>
        public static string Set(string url, KeyValuePair<string, string> param)  {
            return Set(url, new System.Collections.Specialized.NameValueCollection() { 
                { param.Key, param.Value } 
            });
        }
 
        private static void CopyProps(System.Collections.Specialized.NameValueCollection source, System.Collections.Specialized.NameValueCollection destination) { 
            foreach (string key in source) {
                destination[key] = source[key];
            }        
        }
 
        private static string UpdateQuery(string url, Action<System.Collections.Specialized.NameValueCollection> modifyQuery) {
            var uriBuilder = new System.UriBuilder(url);
            var query = System.Web.HttpUtility.ParseQueryString(uriBuilder.Query);
            modifyQuery(query);
            uriBuilder.Query = query.ToString();
            return uriBuilder.Uri.ToString();
        }
    }
}// http://programmingnotes.org/

10. More Examples

Below are more examples demonstrating the use of the ‘Utils‘ Namespace. Don’t forget to include the module when running the examples!





		
		
			More Examples
			
C#
			
			// ============================================================================
//    Author: Kenneth Perkins
//    Date:   May 10, 2021
//    Taken From: http://programmingnotes.org/
//    File:  Program.cs
//    Description: The following demonstrates the use of the Utils Namespace
// ============================================================================
using System;
using System.Diagnostics;
using System.Collections.Generic;

public class Program {
    static void Main(string[] args) {
        try {
            // Declare url
            var url = "http://programmingnotes.org/";

            // Add single key value parameter to the url
            var result = Utils.HttpParams.Add(url, new KeyValuePair<string, string>("ids", "1987"));

            // Display result
            Display(result);

            Display("");

            // Declare url
            var url2 = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer";

            // Add multiple key value parameters to the url
            var addition = new System.Collections.Specialized.NameValueCollection() {
                {"ids", "2010"},
                {"ids", "2019"},
                {"names", "Lynn"},
                {"names", "Sole"}
            };

            // Update the url
            var result2 = Utils.HttpParams.Add(url2, addition);

            // Display result
            Display(result2);

            Display("");

            // Declare url
            var url3 = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer";

            // Remove single parameter from the url
            var result3 = Utils.HttpParams.Remove(url3, "names");

            // Display result
            Display(result3);

            Display("");

            // Declare url
            var url4 = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer";

            // Remove multiple parameters from the url
            var result4 = Utils.HttpParams.Remove(url4, new string[] { "ids", "names" });

            // Display result
            Display(result4);

            Display("");

            // Declare url
            var url5 = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer";

            // Remove multiple parameters from the url
            var result5 = Utils.HttpParams.Clear(url5);

            // Display result
            Display(result5);
            
            Display("");

            // Declare url
            var url6 = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer";

            // Get parameters from the url
            var result6 = Utils.HttpParams.Get(url6);

            // Display result
            foreach (string key in result6) { 
                Display($"Parameter: {key}, Value: {result6[key]}");
            }

            Display("");

            // Declare url
            var url7 = "http://programmingnotes.org/?ids=1987";

            // Update single key value parameter to the url
            var result7 = Utils.HttpParams.Update(url7, new KeyValuePair<string, string>("ids", "1991"));

            // Display result
            Display(result7);

            Display("");

            // Declare url
            var url8 = "http://programmingnotes.org/?ids=1987&names=Kenneth";

            // Update multiple key value parameters to the url
            var addition8 = new System.Collections.Specialized.NameValueCollection() {
                {"ids", "1991"},
                {"ids", "2019"},
                {"names", "Jennifer"},
                {"names", "Sole"}
            };

            // Update the url
            var result8 = Utils.HttpParams.Update(url8, addition8);

            // Display result
            Display(result8);
            
            Display("");
            
            // Declare url
            var url9 = "http://programmingnotes.org/?ids=1987&names=Kenneth";

            // Set multiple key value parameters to the url
            var addition9 = new System.Collections.Specialized.NameValueCollection() {
                {"ids", "1991"},
                {"ids", "2010"},
                {"ids", "2019"},
                {"names", "Jennifer"},
                {"names", "Lynn"},
                {"names", "Sole"}
            };

            // Update the url
            var result9 = Utils.HttpParams.Set(url9, addition9);

            // Display result
            Display(result9);
        } catch (Exception ex) {
            Display(ex.ToString());
        } finally {
            Console.ReadLine();
        }
    }

    static void Display(string message) {
        Console.WriteLine(message);
        Debug.Print(message);
    }
}// http://programmingnotes.org/
			
				
					
				
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						// ============================================================================
//    Author: Kenneth Perkins
//    Date:   May 10, 2021
//    Taken From: http://programmingnotes.org/
//    File:  Program.cs
//    Description: The following demonstrates the use of the Utils Namespace
// ============================================================================
using System;
using System.Diagnostics;
using System.Collections.Generic;
 
public class Program {
    static void Main(string[] args) {
        try {
            // Declare url
            var url = "http://programmingnotes.org/";
 
            // Add single key value parameter to the url
            var result = Utils.HttpParams.Add(url, new KeyValuePair<string, string>("ids", "1987"));
 
            // Display result
            Display(result);
 
            Display("");
 
            // Declare url
            var url2 = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer";
 
            // Add multiple key value parameters to the url
            var addition = new System.Collections.Specialized.NameValueCollection() {
                {"ids", "2010"},
                {"ids", "2019"},
                {"names", "Lynn"},
                {"names", "Sole"}
            };
 
            // Update the url
            var result2 = Utils.HttpParams.Add(url2, addition);
 
            // Display result
            Display(result2);
 
            Display("");
 
            // Declare url
            var url3 = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer";
 
            // Remove single parameter from the url
            var result3 = Utils.HttpParams.Remove(url3, "names");
 
            // Display result
            Display(result3);
 
            Display("");
 
            // Declare url
            var url4 = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer";
 
            // Remove multiple parameters from the url
            var result4 = Utils.HttpParams.Remove(url4, new string[] { "ids", "names" });
 
            // Display result
            Display(result4);
 
            Display("");
 
            // Declare url
            var url5 = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer";
 
            // Remove multiple parameters from the url
            var result5 = Utils.HttpParams.Clear(url5);
 
            // Display result
            Display(result5);
            
            Display("");
 
            // Declare url
            var url6 = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer";
 
            // Get parameters from the url
            var result6 = Utils.HttpParams.Get(url6);
 
            // Display result
            foreach (string key in result6) { 
                Display($"Parameter: {key}, Value: {result6[key]}");
            }
 
            Display("");
 
            // Declare url
            var url7 = "http://programmingnotes.org/?ids=1987";
 
            // Update single key value parameter to the url
            var result7 = Utils.HttpParams.Update(url7, new KeyValuePair<string, string>("ids", "1991"));
 
            // Display result
            Display(result7);
 
            Display("");
 
            // Declare url
            var url8 = "http://programmingnotes.org/?ids=1987&names=Kenneth";
 
            // Update multiple key value parameters to the url
            var addition8 = new System.Collections.Specialized.NameValueCollection() {
                {"ids", "1991"},
                {"ids", "2019"},
                {"names", "Jennifer"},
                {"names", "Sole"}
            };
 
            // Update the url
            var result8 = Utils.HttpParams.Update(url8, addition8);
 
            // Display result
            Display(result8);
            
            Display("");
            
            // Declare url
            var url9 = "http://programmingnotes.org/?ids=1987&names=Kenneth";
 
            // Set multiple key value parameters to the url
            var addition9 = new System.Collections.Specialized.NameValueCollection() {
                {"ids", "1991"},
                {"ids", "2010"},
                {"ids", "2019"},
                {"names", "Jennifer"},
                {"names", "Lynn"},
                {"names", "Sole"}
            };
 
            // Update the url
            var result9 = Utils.HttpParams.Set(url9, addition9);
 
            // Display result
            Display(result9);
        } catch (Exception ex) {
            Display(ex.ToString());
        } finally {
            Console.ReadLine();
        }
    }
 
    static void Display(string message) {
        Console.WriteLine(message);
        Debug.Print(message);
    }
}// http://programmingnotes.org/

QUICK NOTES:
The highlighted lines are sections of interest to look out for.

The code is heavily commented, so no further insight is necessary. If you have any questions, feel free to leave a comment below.

VB.NET || How To Get, Add, Update & Remove Values From A URL Query String Using VB.NET

November 17, 2020 admin No comments

The following is a module with functions which demonstrates how to get, add, update and remove parameters from a query string using C#.

The following functions use System.Web to modify the url.

To use the functions in this module, make sure you have a reference to ‘System.Web‘ in your project.

Note: Don’t forget to include the ‘Utils Namespace‘ before running the examples!

1. Add – Single Parameter

The example below demonstrates the use of ‘Utils.HttpParams.Add‘ to add a query string parameter to a url.





		
		
			1. Add - Single Parameter
			
Visual Basic .NET
			
			' Add - Single Parameter

' Declare url
Dim url = "http://programmingnotes.org/"

' Add single key value parameter to the url
Dim result = Utils.HttpParams.Add(url, New KeyValuePair(Of String, String)("ids", "1987"))

' Display result
Debug.Print(result)

' expected output:
'    http://programmingnotes.org/?ids=1987
			
				
					
				
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						' Add - Single Parameter
 
' Declare url
Dim url = "http://programmingnotes.org/"
 
' Add single key value parameter to the url
Dim result = Utils.HttpParams.Add(url, New KeyValuePair(Of String, String)("ids", "1987"))
 
' Display result
Debug.Print(result)
 
' expected output:
'    http://programmingnotes.org/?ids=1987

2. Add – Multiple Parameters

The example below demonstrates the use of ‘Utils.HttpParams.Add‘ to add a query string parameter to a url.





		
		
			2. Add - Multiple Parameters
			
Visual Basic .NET
			
			' Add - Multiple Parameters

' Declare url
Dim url = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer"

' Add multiple key value parameters to the url
Dim addition = New System.Collections.Specialized.NameValueCollection() From {
    {"ids", "2010"},
    {"ids", "2019"},
    {"names", "Lynn"},
    {"names", "Sole"}
}

' Update the url
Dim result = Utils.HttpParams.Add(url, addition)

' Display result
Debug.Print(result)

' expected output:
'    http://programmingnotes.org/?ids=1987%2c1991%2c2010%2c2019&names=Kenneth%2cJennifer%2cLynn%2cSole
			
				
					
				
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						' Add - Multiple Parameters
 
' Declare url
Dim url = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer"
 
' Add multiple key value parameters to the url
Dim addition = New System.Collections.Specialized.NameValueCollection() From {
    {"ids", "2010"},
    {"ids", "2019"},
    {"names", "Lynn"},
    {"names", "Sole"}
}
 
' Update the url
Dim result = Utils.HttpParams.Add(url, addition)
 
' Display result
Debug.Print(result)
 
' expected output:
'    http://programmingnotes.org/?ids=1987%2c1991%2c2010%2c2019&names=Kenneth%2cJennifer%2cLynn%2cSole

3. Update – Single Parameter

The example below demonstrates the use of ‘Utils.HttpParams.Update‘ to update a query string parameter to a url.





		
		
			3. Update - Single Parameter
			
Visual Basic .NET
			
			' Update - Single Parameter

' Declare url
Dim url = "http://programmingnotes.org/?ids=1987"

' Update single key value parameter to the url
Dim result = Utils.HttpParams.Update(url7, New KeyValuePair(Of String, String)("ids", "1991"))

' Display result
Debug.Print(result)

' expected output:
'    http://programmingnotes.org/?ids=1991
			
				
					
				
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						' Update - Single Parameter
 
' Declare url
Dim url = "http://programmingnotes.org/?ids=1987"
 
' Update single key value parameter to the url
Dim result = Utils.HttpParams.Update(url7, New KeyValuePair(Of String, String)("ids", "1991"))
 
' Display result
Debug.Print(result)
 
' expected output:
'    http://programmingnotes.org/?ids=1991

4. Update – Multiple Parameters

The example below demonstrates the use of ‘Utils.HttpParams.Update‘ to update a query string parameter to a url.





		
		
			4. Update - Multiple Parameters
			
Visual Basic .NET
			
			' Update - Multiple Parameters

' Declare url
Dim url = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer"

' Update multiple key value parameters to the url
Dim addition = New System.Collections.Specialized.NameValueCollection() From {
    {"ids", "2010"},
    {"ids", "2019"},
    {"names", "Lynn"},
    {"names", "Sole"}
}

' Update the url
Dim result = Utils.HttpParams.Update(url, addition)

' Display result
Debug.Print(result)

' expected output:
'    http://programmingnotes.org/?ids=2010%2c2019&names=Lynn%2cSole
			
				
					
				
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						' Update - Multiple Parameters
 
' Declare url
Dim url = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer"
 
' Update multiple key value parameters to the url
Dim addition = New System.Collections.Specialized.NameValueCollection() From {
    {"ids", "2010"},
    {"ids", "2019"},
    {"names", "Lynn"},
    {"names", "Sole"}
}
 
' Update the url
Dim result = Utils.HttpParams.Update(url, addition)
 
' Display result
Debug.Print(result)
 
' expected output:
'    http://programmingnotes.org/?ids=2010%2c2019&names=Lynn%2cSole

5. Remove – Single Parameter

The example below demonstrates the use of ‘Utils.HttpParams.Remove‘ to remove a query string parameter from a url.





		
		
			5. Remove - Single Parameter
			
Visual Basic .NET
			
			' Remove - Single Parameter

' Declare url
Dim url = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer"

' Remove single parameter from the url
Dim result = Utils.HttpParams.Remove(url, "names")

' Display result
Debug.Print(result)

' expected output:
'    http://programmingnotes.org/?ids=1987%2c1991
			
				
					
				
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						' Remove - Single Parameter
 
' Declare url
Dim url = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer"
 
' Remove single parameter from the url
Dim result = Utils.HttpParams.Remove(url, "names")
 
' Display result
Debug.Print(result)
 
' expected output:
'    http://programmingnotes.org/?ids=1987%2c1991

6. Remove – Multiple Parameters

The example below demonstrates the use of ‘Utils.HttpParams.Remove‘ to remove multiple query string parameters from a url.





		
		
			6. Remove - Multiple Parameters
			
Visual Basic .NET
			
			' Remove - Multiple Parameters

' Declare url
Dim url = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer"

' Remove multiple parameters from the url
Dim result = Utils.HttpParams.Remove(url, New String() {"ids", "names"})

' Display result
Debug.Print(result)

' expected output:
'    http://programmingnotes.org/
			
				
					
				
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						' Remove - Multiple Parameters
 
' Declare url
Dim url = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer"
 
' Remove multiple parameters from the url
Dim result = Utils.HttpParams.Remove(url, New String() {"ids", "names"})
 
' Display result
Debug.Print(result)
 
' expected output:
'    http://programmingnotes.org/

7. Clear – Remove All Parameters

The example below demonstrates the use of ‘Utils.HttpParams.Clear‘ to remove all query string parameters from a url.





		
		
			7. Clear - Remove All Parameters
			
Visual Basic .NET
			
			' Clear - Remove All Parameters

' Declare url
Dim url = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer"

' Remove multiple parameters from the url
Dim result = Utils.HttpParams.Clear(url)

' Display result
Debug.Print(result)

' expected output:
'    http://programmingnotes.org/
			
				
					
				
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						' Clear - Remove All Parameters
 
' Declare url
Dim url = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer"
 
' Remove multiple parameters from the url
Dim result = Utils.HttpParams.Clear(url)
 
' Display result
Debug.Print(result)
 
' expected output:
'    http://programmingnotes.org/

8. Get – Get All Parameters

The example below demonstrates the use of ‘Utils.HttpParams.Get‘ to get all query string parameters from a url.





		
		
			8. Get - Get All Parameters
			
Visual Basic .NET
			
			' Get - Get All Parameters

' Declare url
Dim url = "http://programmingnotes.org/?ids=1987,1991,2010,2019&names=Kenneth,Jennifer,Lynn,Sole"

' Get parameters from the url
Dim result = Utils.HttpParams.Get(url)

' Display result
For Each key As String In result
    Debug.Print($"Parameter: {key}, Value: {result(key)}")
Next

' expected output:
'    Parameter: ids, Value: 1987,1991,2010,2019
'    Parameter: names, Value: Kenneth,Jennifer,Lynn,Sole
			
				
					
				
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						' Get - Get All Parameters
 
' Declare url
Dim url = "http://programmingnotes.org/?ids=1987,1991,2010,2019&names=Kenneth,Jennifer,Lynn,Sole"
 
' Get parameters from the url
Dim result = Utils.HttpParams.Get(url)
 
' Display result
For Each key As String In result
    Debug.Print($"Parameter: {key}, Value: {result(key)}")
Next
 
' expected output:
'    Parameter: ids, Value: 1987,1991,2010,2019
'    Parameter: names, Value: Kenneth,Jennifer,Lynn,Sole

9. Utils Namespace

The following is the Utils Namespace. Include this in your project to start using!





		
		
			Utils Namespace
			
Visual Basic .NET
			
			' ============================================================================
'    Author: Kenneth Perkins
'    Date:   Nov 17, 2020
'    Taken From: http://programmingnotes.org/
'    File: Utils.vb
'    Description: Handles general utility functions
' ============================================================================
Option Strict On
Option Explicit On

Namespace Global.Utils
    Namespace HttpParams
        Public Module modHttpParams
            ''' <summary>
            ''' Adds the query string parameters to a url
            ''' </summary>
            ''' <param name="url">The url to append parameters</param> 
            ''' <param name="query">The parameters to add to the url</param> 
            ''' <returns>The url appended with the specified query</returns>
            Function Add(url As String, query As System.Collections.Specialized.NameValueCollection) As String
                Return UpdateQuery(url, Sub(queryString)
                                            Dim merged = New System.Collections.Specialized.NameValueCollection From {
                                                queryString,
                                                query
                                            }
                                            CopyProps(merged, queryString)
                                        End Sub)
            End Function

            ''' <summary>
            ''' Adds the query string parameters to a url
            ''' </summary>
            ''' <param name="url">The url to append parameters</param> 
            ''' <param name="param">The parameters to add to the url</param> 
            ''' <returns>The url appended with the specified query</returns>
            Function Add(url As String, param As KeyValuePair(Of String, String)) As String
                Return Add(url, New System.Collections.Specialized.NameValueCollection() From {
                    {param.Key, param.Value}
                })
            End Function

            ''' <summary>
            ''' Updates the query string parameters to a url
            ''' </summary>
            ''' <param name="url">The url to update parameters</param> 
            ''' <param name="query">The parameters to update to the url</param> 
            ''' <returns>The url updated with the specified query</returns>
            Function Update(url As String, query As System.Collections.Specialized.NameValueCollection) As String
                Return UpdateQuery(url, Sub(queryString)
                                            CopyProps(query, queryString)
                                        End Sub)
            End Function

            ''' <summary>
            ''' Updates the query string parameters to a url
            ''' </summary>
            ''' <param name="url">The url to update parameters</param> 
            ''' <param name="param">The parameters to update to the url</param> 
            ''' <returns>The url updated with the specified query</returns>
            Function Update(url As String, param As KeyValuePair(Of String, String)) As String
                Return Update(url, New System.Collections.Specialized.NameValueCollection() From {
                    {param.Key, param.Value}
                })
            End Function

            ''' <summary>
            ''' Removes the parameters with the matching keys from the query string of a url
            ''' </summary>
            ''' <param name="url">The url to remove parameters</param> 
            ''' <param name="keys">The parameter keys to remove from the url</param> 
            ''' <returns>The url with the parameters removed</returns>
            Function Remove(url As String, keys As IEnumerable(Of String)) As String
                Return UpdateQuery(url, Sub(queryString)
                                            For Each key In keys
                                                If queryString.AllKeys.Contains(key) Then
                                                    queryString.Remove(key)
                                                End If
                                            Next
                                        End Sub)
            End Function

            ''' <summary>
            ''' Removes the parameter with the matching key from the query string of a url
            ''' </summary>
            ''' <param name="url">The url to remove a parameter</param> 
            ''' <param name="key">The parameter key to remove from the url</param> 
            ''' <returns>The url with the parameter removed</returns>
            Function Remove(url As String, key As String) As String
                Return Remove(url, New String() {key})
            End Function

            ''' <summary>
            ''' Removes all parameters from the query string of a url
            ''' </summary>
            ''' <param name="url">The url to clear parameters</param>  
            ''' <returns>The url with the parameters removed</returns>
            Function Clear(url As String) As String
                Return UpdateQuery(url, Sub(queryString)
                                            queryString.Clear()
                                        End Sub)
            End Function

            ''' <summary>
            ''' Returns all parameters from the query string of a url
            ''' </summary>
            ''' <param name="url">The url to get parameters</param>  
            ''' <returns>The url parameters</returns>
            Function [Get](url As String) As System.Collections.Specialized.NameValueCollection
                Dim result As System.Collections.Specialized.NameValueCollection = Nothing
                UpdateQuery(url, Sub(queryString)
                                     result = queryString
                                 End Sub)
                Return result
            End Function

            ''' <summary>
            ''' Sets the query string parameters to a url
            ''' </summary>
            ''' <param name="url">The url to set parameters</param> 
            ''' <param name="query">The parameters to set to the url</param> 
            ''' <returns>The url set with the specified query</returns>
            Function [Set](url As String, query As System.Collections.Specialized.NameValueCollection) As String
                url = Clear(url)
                Return Add(url, query)
            End Function

            ''' <summary>
            ''' Sets the query string parameters to a url
            ''' </summary>
            ''' <param name="url">The url to set parameters</param> 
            ''' <param name="param">The parameters to set to the url</param> 
            ''' <returns>The url set with the specified query</returns>
            Function [Set](url As String, param As KeyValuePair(Of String, String)) As String
                Return [Set](url, New System.Collections.Specialized.NameValueCollection() From {
                    {param.Key, param.Value}
                })
            End Function

            Private Sub CopyProps(source As System.Collections.Specialized.NameValueCollection, destination As System.Collections.Specialized.NameValueCollection)
                For Each key As String In source
                    destination(key) = source(key)
                Next
            End Sub

            Private Function UpdateQuery(url As String, modifyQuery As Action(Of System.Collections.Specialized.NameValueCollection)) As String
                Dim uriBuilder = New System.UriBuilder(url)
                Dim query = System.Web.HttpUtility.ParseQueryString(uriBuilder.Query)
                modifyQuery(query)
                uriBuilder.Query = query.ToString()
                Return uriBuilder.Uri.ToString()
            End Function
        End Module
    End Namespace
End Namespace ' http://programmingnotes.org/
			
				
					
				
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						' ============================================================================
'    Author: Kenneth Perkins
'    Date:   Nov 17, 2020
'    Taken From: http://programmingnotes.org/
'    File: Utils.vb
'    Description: Handles general utility functions
' ============================================================================
Option Strict On
Option Explicit On
 
Namespace Global.Utils
    Namespace HttpParams
        Public Module modHttpParams
            ''' <summary>
            ''' Adds the query string parameters to a url
            ''' </summary>
            ''' <param name="url">The url to append parameters</param> 
            ''' <param name="query">The parameters to add to the url</param> 
            ''' <returns>The url appended with the specified query</returns>
            Function Add(url As String, query As System.Collections.Specialized.NameValueCollection) As String
                Return UpdateQuery(url, Sub(queryString)
                                            Dim merged = New System.Collections.Specialized.NameValueCollection From {
                                                queryString,
                                                query
                                            }
                                            CopyProps(merged, queryString)
                                        End Sub)
            End Function
 
            ''' <summary>
            ''' Adds the query string parameters to a url
            ''' </summary>
            ''' <param name="url">The url to append parameters</param> 
            ''' <param name="param">The parameters to add to the url</param> 
            ''' <returns>The url appended with the specified query</returns>
            Function Add(url As String, param As KeyValuePair(Of String, String)) As String
                Return Add(url, New System.Collections.Specialized.NameValueCollection() From {
                    {param.Key, param.Value}
                })
            End Function
 
            ''' <summary>
            ''' Updates the query string parameters to a url
            ''' </summary>
            ''' <param name="url">The url to update parameters</param> 
            ''' <param name="query">The parameters to update to the url</param> 
            ''' <returns>The url updated with the specified query</returns>
            Function Update(url As String, query As System.Collections.Specialized.NameValueCollection) As String
                Return UpdateQuery(url, Sub(queryString)
                                            CopyProps(query, queryString)
                                        End Sub)
            End Function
 
            ''' <summary>
            ''' Updates the query string parameters to a url
            ''' </summary>
            ''' <param name="url">The url to update parameters</param> 
            ''' <param name="param">The parameters to update to the url</param> 
            ''' <returns>The url updated with the specified query</returns>
            Function Update(url As String, param As KeyValuePair(Of String, String)) As String
                Return Update(url, New System.Collections.Specialized.NameValueCollection() From {
                    {param.Key, param.Value}
                })
            End Function
 
            ''' <summary>
            ''' Removes the parameters with the matching keys from the query string of a url
            ''' </summary>
            ''' <param name="url">The url to remove parameters</param> 
            ''' <param name="keys">The parameter keys to remove from the url</param> 
            ''' <returns>The url with the parameters removed</returns>
            Function Remove(url As String, keys As IEnumerable(Of String)) As String
                Return UpdateQuery(url, Sub(queryString)
                                            For Each key In keys
                                                If queryString.AllKeys.Contains(key) Then
                                                    queryString.Remove(key)
                                                End If
                                            Next
                                        End Sub)
            End Function
 
            ''' <summary>
            ''' Removes the parameter with the matching key from the query string of a url
            ''' </summary>
            ''' <param name="url">The url to remove a parameter</param> 
            ''' <param name="key">The parameter key to remove from the url</param> 
            ''' <returns>The url with the parameter removed</returns>
            Function Remove(url As String, key As String) As String
                Return Remove(url, New String() {key})
            End Function
 
            ''' <summary>
            ''' Removes all parameters from the query string of a url
            ''' </summary>
            ''' <param name="url">The url to clear parameters</param>  
            ''' <returns>The url with the parameters removed</returns>
            Function Clear(url As String) As String
                Return UpdateQuery(url, Sub(queryString)
                                            queryString.Clear()
                                        End Sub)
            End Function
 
            ''' <summary>
            ''' Returns all parameters from the query string of a url
            ''' </summary>
            ''' <param name="url">The url to get parameters</param>  
            ''' <returns>The url parameters</returns>
            Function [Get](url As String) As System.Collections.Specialized.NameValueCollection
                Dim result As System.Collections.Specialized.NameValueCollection = Nothing
                UpdateQuery(url, Sub(queryString)
                                     result = queryString
                                 End Sub)
                Return result
            End Function
 
            ''' <summary>
            ''' Sets the query string parameters to a url
            ''' </summary>
            ''' <param name="url">The url to set parameters</param> 
            ''' <param name="query">The parameters to set to the url</param> 
            ''' <returns>The url set with the specified query</returns>
            Function [Set](url As String, query As System.Collections.Specialized.NameValueCollection) As String
                url = Clear(url)
                Return Add(url, query)
            End Function
 
            ''' <summary>
            ''' Sets the query string parameters to a url
            ''' </summary>
            ''' <param name="url">The url to set parameters</param> 
            ''' <param name="param">The parameters to set to the url</param> 
            ''' <returns>The url set with the specified query</returns>
            Function [Set](url As String, param As KeyValuePair(Of String, String)) As String
                Return [Set](url, New System.Collections.Specialized.NameValueCollection() From {
                    {param.Key, param.Value}
                })
            End Function
 
            Private Sub CopyProps(source As System.Collections.Specialized.NameValueCollection, destination As System.Collections.Specialized.NameValueCollection)
                For Each key As String In source
                    destination(key) = source(key)
                Next
            End Sub
 
            Private Function UpdateQuery(url As String, modifyQuery As Action(Of System.Collections.Specialized.NameValueCollection)) As String
                Dim uriBuilder = New System.UriBuilder(url)
                Dim query = System.Web.HttpUtility.ParseQueryString(uriBuilder.Query)
                modifyQuery(query)
                uriBuilder.Query = query.ToString()
                Return uriBuilder.Uri.ToString()
            End Function
        End Module
    End Namespace
End Namespace ' http://programmingnotes.org/

10. More Examples

Below are more examples demonstrating the use of the ‘Utils‘ Namespace. Don’t forget to include the module when running the examples!





		
		
			More Examples
			
Visual Basic .NET
			
			' ============================================================================
'    Author: Kenneth Perkins
'    Date:   Nov 17, 2020
'    Taken From: http://programmingnotes.org/
'    File: Program.vb
'    Description: The following demonstrates the use of the Utils Namespace
' ============================================================================
Option Strict On
Option Explicit On
Imports System

Public Module Program
    Sub Main(args As String())
        Try
            ' Declare url
            Dim url = "http://programmingnotes.org/"

            ' Add single key value parameter to the url
            Dim result = Utils.HttpParams.Add(url, New KeyValuePair(Of String, String)("ids", "1987"))

            ' Display result
            Display(result)

            Display("")

            ' Declare url
            Dim url2 = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer"

            ' Add multiple key value parameters to the url
            Dim addition = New System.Collections.Specialized.NameValueCollection() From {
                {"ids", "2010"},
                {"ids", "2019"},
                {"names", "Lynn"},
                {"names", "Sole"}
            }

            ' Update the url
            Dim result2 = Utils.HttpParams.Add(url2, addition)

            ' Display result
            Display(result2)

            Display("")

            ' Declare url
            Dim url3 = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer"

            ' Remove single parameter from the url
            Dim result3 = Utils.HttpParams.Remove(url3, "names")

            ' Display result
            Display(result3)

            Display("")

            ' Declare url
            Dim url4 = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer"

            ' Remove multiple parameters from the url
            Dim result4 = Utils.HttpParams.Remove(url4, New String() {"ids", "names"})

            ' Display result
            Display(result4)

            Display("")

            ' Declare url
            Dim url5 = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer"

            ' Remove multiple parameters from the url
            Dim result5 = Utils.HttpParams.Clear(url5)

            ' Display result
            Display(result5)

            Display("")

            ' Declare url
            Dim url6 = "http://programmingnotes.org/?ids=1987,1991,2010,2019&names=Kenneth,Jennifer,Lynn,Sole"

            ' Get parameters from the url
            Dim result6 = Utils.HttpParams.Get(url6)

            ' Display result
            For Each key As String In result6
                Display($"Parameter: {key}, Value: {result6(key)}")
            Next

            Display("")

            ' Declare url
            Dim url7 = "http://programmingnotes.org/?ids=1987"

            ' Update single key value parameter to the url
            Dim result7 = Utils.HttpParams.Update(url7, New KeyValuePair(Of String, String)("ids", "1991"))

            ' Display result
            Display(result7)

            Display("")

            ' Declare url
            Dim url8 = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer"

            ' Update multiple key value parameters to the url
            Dim addition8 = New System.Collections.Specialized.NameValueCollection() From {
                {"ids", "2010"},
                {"ids", "2019"},
                {"names", "Lynn"},
                {"names", "Sole"}
            }

            ' Update the url
            Dim result8 = Utils.HttpParams.Update(url8, addition8)

            ' Display result
            Display(result8)

            Display("")

            ' Declare url
            Dim url9 = "http://programmingnotes.org/?ids=1987&names=Kenneth"

            ' Set multiple key value parameters to the url
            Dim addition9 = New System.Collections.Specialized.NameValueCollection() From {
                {"ids", "1991"},
                {"ids", "2010"},
                {"ids", "2019"},
                {"names", "Jennifer"},
                {"names", "Lynn"},
                {"names", "Sole"}
            }

            ' Update the url
            Dim result9 = Utils.HttpParams.Set(url9, addition9)

            ' Display result
            Display(result9)
        Catch ex As Exception
            Display(ex.ToString)
        Finally
            Console.ReadLine()
        End Try
    End Sub

    Public Sub Display(message As String)
        Console.WriteLine(message)
        Debug.Print(message)
    End Sub
End Module ' http://programmingnotes.org/
			
				
					
				
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						' ============================================================================
'    Author: Kenneth Perkins
'    Date:   Nov 17, 2020
'    Taken From: http://programmingnotes.org/
'    File: Program.vb
'    Description: The following demonstrates the use of the Utils Namespace
' ============================================================================
Option Strict On
Option Explicit On
Imports System
 
Public Module Program
    Sub Main(args As String())
        Try
            ' Declare url
            Dim url = "http://programmingnotes.org/"
 
            ' Add single key value parameter to the url
            Dim result = Utils.HttpParams.Add(url, New KeyValuePair(Of String, String)("ids", "1987"))
 
            ' Display result
            Display(result)
 
            Display("")
 
            ' Declare url
            Dim url2 = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer"
 
            ' Add multiple key value parameters to the url
            Dim addition = New System.Collections.Specialized.NameValueCollection() From {
                {"ids", "2010"},
                {"ids", "2019"},
                {"names", "Lynn"},
                {"names", "Sole"}
            }
 
            ' Update the url
            Dim result2 = Utils.HttpParams.Add(url2, addition)
 
            ' Display result
            Display(result2)
 
            Display("")
 
            ' Declare url
            Dim url3 = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer"
 
            ' Remove single parameter from the url
            Dim result3 = Utils.HttpParams.Remove(url3, "names")
 
            ' Display result
            Display(result3)
 
            Display("")
 
            ' Declare url
            Dim url4 = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer"
 
            ' Remove multiple parameters from the url
            Dim result4 = Utils.HttpParams.Remove(url4, New String() {"ids", "names"})
 
            ' Display result
            Display(result4)
 
            Display("")
 
            ' Declare url
            Dim url5 = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer"
 
            ' Remove multiple parameters from the url
            Dim result5 = Utils.HttpParams.Clear(url5)
 
            ' Display result
            Display(result5)
 
            Display("")
 
            ' Declare url
            Dim url6 = "http://programmingnotes.org/?ids=1987,1991,2010,2019&names=Kenneth,Jennifer,Lynn,Sole"
 
            ' Get parameters from the url
            Dim result6 = Utils.HttpParams.Get(url6)
 
            ' Display result
            For Each key As String In result6
                Display($"Parameter: {key}, Value: {result6(key)}")
            Next
 
            Display("")
 
            ' Declare url
            Dim url7 = "http://programmingnotes.org/?ids=1987"
 
            ' Update single key value parameter to the url
            Dim result7 = Utils.HttpParams.Update(url7, New KeyValuePair(Of String, String)("ids", "1991"))
 
            ' Display result
            Display(result7)
 
            Display("")
 
            ' Declare url
            Dim url8 = "http://programmingnotes.org/?ids=1987,1991&names=Kenneth,Jennifer"
 
            ' Update multiple key value parameters to the url
            Dim addition8 = New System.Collections.Specialized.NameValueCollection() From {
                {"ids", "2010"},
                {"ids", "2019"},
                {"names", "Lynn"},
                {"names", "Sole"}
            }
 
            ' Update the url
            Dim result8 = Utils.HttpParams.Update(url8, addition8)
 
            ' Display result
            Display(result8)
 
            Display("")
 
            ' Declare url
            Dim url9 = "http://programmingnotes.org/?ids=1987&names=Kenneth"
 
            ' Set multiple key value parameters to the url
            Dim addition9 = New System.Collections.Specialized.NameValueCollection() From {
                {"ids", "1991"},
                {"ids", "2010"},
                {"ids", "2019"},
                {"names", "Jennifer"},
                {"names", "Lynn"},
                {"names", "Sole"}
            }
 
            ' Update the url
            Dim result9 = Utils.HttpParams.Set(url9, addition9)
 
            ' Display result
            Display(result9)
        Catch ex As Exception
            Display(ex.ToString)
        Finally
            Console.ReadLine()
        End Try
    End Sub
 
    Public Sub Display(message As String)
        Console.WriteLine(message)
        Debug.Print(message)
    End Sub
End Module ' http://programmingnotes.org/

QUICK NOTES:
The highlighted lines are sections of interest to look out for.

The code is heavily commented, so no further insight is necessary. If you have any questions, feel free to leave a comment below.

Tag Archives: update querystring

C# || How To Get, Add, Update & Remove Values From A URL Query String Using C#

VB.NET || How To Get, Add, Update & Remove Values From A URL Query String Using VB.NET

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