Send POST with WebClient.DownloadString in C#

问题:

I know there are a lot of questions about sending HTTP POST requests with C#, but I'm looking for a method that uses WebClient rather than HttpWebRequest. Is this possible? It'd be nice because the WebClient class is so easy to use.

I know I can set the Headers property to have certain headers set, but I don't know if it's possible to actually do a POST from WebClient.

回答1:

You can use WebClient.UploadData() which uses HTTP POST, i.e.:

using (WebClient wc = new WebClient())
{
    byte[] result = wc.UploadData("http://stackoverflow.com", new byte[] { });
}

The payload data that you specify will be transmitted as the POST body of your request.

Alternatively there is WebClient.UploadValues() to upload a name-value collection also via HTTP POST.

回答2:

You could use Upload method with HTTP 1.0 POST

string postData = Console.ReadLine();

using (System.Net.WebClient wc = new System.Net.WebClient())
{
    wc.Headers.Add("Content-Type","application/x-www-form-urlencoded");
    // Upload the input string using the HTTP 1.0 POST method.
    byte[] byteArray = System.Text.Encoding.ASCII.GetBytes(postData);
    byte[] byteResult= wc.UploadData("http://targetwebiste","POST",byteArray);
    // Decode and display the result.
    Console.WriteLine("\nResult received was {0}",
                      Encoding.ASCII.GetString(byteResult));
}