Send x-www-form-urlencoded Post Request Using HttpClient in C#

Sending HTTP requests to some external endpoints using C# is something I have to do quite often in my projects. We have numerous libraries like RestSharp for this purpose.

In this post, we'll learn to use the  HttpClient class from System.Net.Http to send HTTP requests from C# applications with x-www-form-urlencoded data.

Sending Post Request

To send a post request, we should, first, create an object of the HttpClient class and use its PostAsync() method to send the actual post request.

string endPoint = "https://hookb.in/QJ0QKKD7yzt8mNzzmz2J";
var client = new HttpClient();

In order to send the data in x-www-form-urlencoded format, we can use FormUrlEncodedContent class. It accepts the data as an IEnumerable of KeyValue pairs.

var data = new[]
{
	new KeyValuePair<string, string>("name", "John Doe"),
	new KeyValuePair<string, string>("email", "johndoe@example.com"),
};

Next, we can send the actual post request using the PostAsync method.

await client.PostAsync(endPoint, new FormUrlEncodedContent(data));

If you are not calling this method from an async method, user GetAwaiter().GetResult().

client.PostAsync(endPoint, new FormUrlEncodedContent(data)).GetAwaiter().GetResult();

Here's the complete code.

public static void Main()
{
    string endPoint = "https://hookb.in/QJ0QKKD7yzt8mNzzmz2J";
    var client = new HttpClient();

    var data = new[]
    {
        new KeyValuePair<string, string>("name", "John Doe"),
        new KeyValuePair<string, string>("email", "johndoe@example.com"),
    };
    client.PostAsync(endPoint, new FormUrlEncodedContent(data)).GetAwaiter().GetResult();
}

Check this link to see the request sent from our application.

Happy coding 👍.