How to post data to specific URL using WebClient in C#

Question

I need to use "HTTP Post" with WebClient to post some data to a specific URL I have.

Now, I know this can be accomplished with WebRequest but for some reasons I want to use WebClient instead. Is that possible? If so, can someone show me some example or point me to the right direction?

Solution 1

I just found the solution and yea it was easier than I thought :)

so here is the solution:

string URI = "http://www.myurl.com/post.php";
string myParameters = "param1=value1&param2=value2&param3=value3";

using (WebClient wc = new WebClient())
{
    wc.Headers[HttpRequestHeader.ContentType] = "application/x-www-form-urlencoded";
    string HtmlResult = wc.UploadString(URI, myParameters);
}

it works like charm :)

Solution 2

There is a built in method called UploadValues that can send HTTP POST (or any kind of HTTP methods) AND handles the construction of request body (concatenating parameters with "&" and escaping characters by url encoding) in proper form data format:

using(WebClient client = new WebClient())
{
    var reqparm = new System.Collections.Specialized.NameValueCollection();
    reqparm.Add("param1", "<any> kinds & of = ? strings");
    reqparm.Add("param2", "escaping is already handled");
    byte[] responsebytes = client.UploadValues("http://localhost", "POST", reqparm);
    string responsebody = Encoding.UTF8.GetString(responsebytes);
}

Solution 3

Using WebClient.UploadString or WebClient.UploadData you can POST data to the server easily. I’ll show an example using UploadData, since UploadString is used in the same manner as DownloadString.

byte[] bret = client.UploadData("http://www.website.com/post.php", "POST",
                System.Text.Encoding.ASCII.GetBytes("field1=value1&field2=value2") );
 
string sret = System.Text.Encoding.ASCII.GetString(bret);

More: http://www.daveamenta.com/2008-05/c-webclient-usage/

Solution 4

string URI = "site.com/mail.php";
using (WebClient client = new WebClient())
{
    System.Collections.Specialized.NameValueCollection postData = 
        new System.Collections.Specialized.NameValueCollection()
       {
              { "to", emailTo },  
              { "subject", currentSubject },
              { "body", currentBody }
       };
    string pagesource = Encoding.UTF8.GetString(client.UploadValues(URI, postData));
}

Solution 5

//Making a POST request using WebClient.
Function()
{    
  WebClient wc = new WebClient();

  var URI = new Uri("http://your_uri_goes_here");

  //If any encoding is needed.
  wc.Headers["Content-Type"] = "application/x-www-form-urlencoded";
  //Or any other encoding type.

  //If any key needed

  wc.Headers["KEY"] = "Your_Key_Goes_Here";

  wc.UploadStringCompleted += 
      new UploadStringCompletedEventHandler(wc_UploadStringCompleted);

  wc.UploadStringAsync(URI,"POST","Data_To_Be_sent");    
}

void wc__UploadStringCompleted(object sender, UploadStringCompletedEventArgs e)    
{  
  try            
  {          
     MessageBox.Show(e.Result); 
     //e.result fetches you the response against your POST request.         
  }
  catch(Exception exc)         
  {             
     MessageBox.Show(exc.ToString());            
  }
}

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