WebRequest slow?

I recently tried to do a web request in .NET C#. So I looked it up in the MSDN and wrote down some lines of code and was happy that it worked  straightaway (ok, it’s not very complex anyhow).

It looked something like this:

    string responseContent;
    HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
    request.Method = "GET";

    HttpWebResponse response = (HttpWebResponse)request.GetResponse();

    Stream responseStream = response.GetResponseStream();
    using (StreamReader sr = new StreamReader(responseStream))
        responseContent = sr.ReadToEnd();

    return responseContent;

But this code was very slow and it took several seconds to get the response.
One reason for that is that if you don’t use a proxy or just don’t set the proxy property of the WebRequest, it tries to auto-detect and configure a proxy what causes a significant delay.
So just adding

    request.Proxy = null;

before the GetResponse() call will fix that problem.

Remark/Update: To be more correct, you should set ”request.Proxy = GlobalProxySelection.GetEmptyWebProxy();” instead of just null. (MSDN: HttpWebRequest.Proxy property)

Another point is that you should always close the WebResponse after processing its contents. That might also speed up your requests. I prefer to use “using” statements to do that. It will get a bit nested sometimes but this way you just can’t forget it.
So here’s the final code for a simple “GET” request:

public string MakeWebRequest(string url)
{
    try
    {
        string responseContent;
        HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
        request.Method = "GET";
        request.Proxy = GlobalProxySelection.GetEmptyWebProxy(); // null;

        using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
        {
            using (Stream responseStream = response.GetResponseStream())
            {
                using (StreamReader sr = new StreamReader(responseStream))
                    responseContent = sr.ReadToEnd();
            }
        }

        return responseContent;
    }
    catch (Exception ex)
    {
        // Error handling
        return ex.Message;
    }
}

Extending the code for a “POST” request:

To make a “POST” request we have to add the following:

public string MakeWebRequest(string url, string postData)
{
    try
    {
        string responseContent;
        HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
        // Set Method to "POST"
        request.Method = "POST";
        // Convert "POST" data to a byte array
        byte[] byteArray = Encoding.UTF8.GetBytes(postData);
        // Set the content type of the WebRequest
        request.ContentType = "application/x-www-form-urlencoded";
        // Set the content length
        request.ContentLength = byteArray.Length;
        // Get the request stream
        using (Stream requestStream = request.GetRequestStream())
        {
            // Write the "POST" data to the stream
            requestStream.Write(byteArray, 0, byteArray.Length);
        }
        // Don't forget to set the proxy
        request.Proxy = GlobalProxySelection.GetEmptyWebProxy(); // null;

        using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
        {
            using (Stream responseStream = response.GetResponseStream())
            {
                using (StreamReader sr = new StreamReader(responseStream))
                    responseContent = sr.ReadToEnd();
            }
        }

        return responseContent;
    }
    catch (Exception ex)
    {
        // Error handling
        return ex.Message;
    }
}

public string MakeWebRequest(string url)
{
try
{
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
request.Method = “GET”;
request.Proxy = null;

using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
{
Stream responseStream = response.GetResponseStream();
using (StreamReader sr = new StreamReader(responseStream))
{
string responseContent = sr.ReadToEnd();
return responseContent;
}
}
}
catch (Exception ex)
{
return ex.Message;
}
}

About these ads