title: ajax send request with encoding gzip is not working
body: <p>Ajax send request with encoding gzip (iis7) is not working below are the code for send request
  can some one help me what is wrong in my code.</p>
  
  <p>Thanks in advance</p>
  
  <pre><code>function sendRequest(url, callback, postData)
  {
     var req = createXMLHTTPObject();
     if (!req) {
        return;
     }
  
     var method = (postData) ? "POST" : "GET";
     req.open(method, "xml/" + url, true);
     req.setRequestHeader('User-Agent', 'XMLHTTP/1.0');
  
     if (postData) {
        req.setRequestHeader('Content-type', 'application/x-www-form-urlencoded');
        req.setRequestHeader("Content-Encoding", "gzip");
  
     }
  
     req.onreadystatechange = function() {
  
     }
  
     req.send(postData);
  }
  </code></pre>