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URL parameters in C#

To get the parameter from a URL string in C#, you can use the HttpUtility.ParseQueryString method to parse the query string and then retrieve the value of the desired parameter. Here's an example:

using System;
using System.Web;

string url = "http://example.com/?param1=value1&param2=value2";
Uri uri = new Uri(url);
string queryString = uri.Query;
NameValueCollection queryParameters = HttpUtility.ParseQueryString(queryString);
string param1Value = queryParameters["param1"];
Console.WriteLine(param1Value); // output: value1

To update the parameter value from a URL string in C#, you can modify the NameValueCollection object that represents the query string and then rebuild the URL using the UriBuilder class. Here's an example:

using System;
using System.Web;

string url = "http://example.com/?param1=value1&param2=value2";
UriBuilder uriBuilder = new UriBuilder(url);
NameValueCollection queryParameters = HttpUtility.ParseQueryString(uriBuilder.Query);
queryParameters["param1"] = "newvalue";
uriBuilder.Query = queryParameters.ToString();
string newUrl = uriBuilder.ToString();
Console.WriteLine(newUrl); // output: http://example.com/?param1=newvalue&param2=value2

To create a URL containing redirect URL with parameters as a query string and get it in the server-side by C#, you can use the UriBuilder class to build the URL and append the query string parameters. Here's an example:

using System;

string redirectUrl = "http://example.com/redirect";
string param1 = "value1";
string param2 = "value2";

UriBuilder uriBuilder = new UriBuilder(redirectUrl);
uriBuilder.Query = $"param1={param1}&param2={param2}";

string urlWithParams = uriBuilder.ToString();

// Now you can use the `urlWithParams` string to redirect the user or pass it to a controller action method.

C# URL parameter parsing:

Parsing and extracting parameters from a URL in C#.

Code snippet:

Uri uri = new Uri("https://www.example.com/page?param1=value1&param2=value2");
string paramValue = HttpUtility.ParseQueryString(uri.Query).Get("param1");

C# URL parameter encoding and decoding:

Encoding and decoding URL parameters in C#.

Code snippet:

string originalString = "value with spaces";
string encodedValue = Uri.EscapeDataString(originalString);
string decodedValue = Uri.UnescapeDataString(encodedValue);

C# UriBuilder with parameters:

Using UriBuilder to construct URLs with parameters in C#.

Code snippet:

UriBuilder builder = new UriBuilder("https://www.example.com");
builder.Query = "param1=value1&param2=value2";
Uri uri = builder.Uri;

Constructing URLs with parameters in C#:

Constructing URLs dynamically with parameters in C#.

Code snippet:

string baseUri = "https://www.example.com/page";
string param1 = "value1";
string param2 = "value2";
string constructedUrl = $"{baseUri}?param1={Uri.EscapeDataString(param1)}&param2={Uri.EscapeDataString(param2)}";

C# URL parameter validation:

Validating URL parameters in C#.

Code snippet:

Uri uri;
bool isValidUrl = Uri.TryCreate("https://www.example.com/page?param=value", UriKind.Absolute, out uri);

Query parameter manipulation in C#:

Manipulating query parameters in C#.

Code snippet:

Uri uri = new Uri("https://www.example.com/page?param1=value1&param2=value2");
string updatedQuery = "param3=newValue3";
Uri updatedUri = new UriBuilder(uri) { Query = updatedQuery }.Uri;

Building query strings in C#:

Building query strings dynamically in C#.

Code snippet:

var parameters = new Dictionary<string, string>
{
    { "param1", "value1" },
    { "param2", "value2" }
};
string queryString = string.Join("&", parameters.Select(p => $"{p.Key}={Uri.EscapeDataString(p.Value)}"));

C# get URL parameter values:

Extracting and using URL parameter values in C#.

Code snippet:

Uri uri = new Uri("https://www.example.com/page?param1=value1&param2=value2");
string param1Value = HttpUtility.ParseQueryString(uri.Query).Get("param1");

Handling optional parameters in URL in C#:

Handling optional parameters in a URL in C#.

Code snippet:

Uri uri = new Uri("https://www.example.com/page?param1=value1");
string param1Value = HttpUtility.ParseQueryString(uri.Query).Get("param1") ?? "default";

C# URL parameter mapping:

Mapping URL parameters to variables in C#.

Code snippet:

Uri uri = new Uri("https://www.example.com/page?param1=value1&param2=value2");
string param1 = HttpUtility.ParseQueryString(uri.Query).Get("param1");
string param2 = HttpUtility.ParseQueryString(uri.Query).Get("param2");

Passing parameters in URL in C#:

Passing parameters in a URL in C#.

Code snippet:

string baseUri = "https://www.example.com/page";
string param1 = "value1";
string param2 = "value2";
string finalUrl = $"{baseUri}/{param1}/{param2}";

C# URL parameter array:

Handling URL parameters as arrays in C#.

Code snippet:

Uri uri = new Uri("https://www.example.com/page?param=value1&param=value2");
string[] paramValues = HttpUtility.ParseQueryString(uri.Query).GetValues("param");

Query parameter serialization in C#:

Serializing query parameters in C#.

Code snippet:

var parameters = new Dictionary<string, string>
{
    { "param1", "value1" },
    { "param2", "value2" }
};
string serializedParameters = JsonConvert.SerializeObject(parameters);