Asynchronous HttpWebRequest in .NET with C#

This guide explains how to asynchronously invoke HttpWebRequest in .NET using C#. .NET's asynchronous programming model allows for concurrent task execution without blocking the main thread, leading to more responsive applications.

The key to asynchronous HTTP requests is the HttpWebRequest.BeginGetResponse method. This initiates the request and immediately returns control, allowing other operations to proceed while the request is processed in the background.

Here's a code example demonstrating asynchronous HTTP request initiation using BeginGetResponse:

HttpWebRequest webRequest;

void StartWebRequest()
{
    webRequest.BeginGetResponse(new AsyncCallback(FinishWebRequest), null);
}

void FinishWebRequest(IAsyncResult result)
{
    webRequest.EndGetResponse(result);
}

BeginGetResponse accepts an AsyncCallback delegate as its first argument. This delegate points to the method called upon asynchronous operation completion – in this example, FinishWebRequest.

The FinishWebRequest callback handles the asynchronous operation's result. It uses EndGetResponse to retrieve and process the response.

Employing HttpWebRequest's asynchronous capabilities enhances application performance and responsiveness by preventing HTTP requests from blocking the main execution thread.