title: What is transformRequest in angularjs
body: <p>I have a code</p>
  
  <pre><code> transformRequest: function(obj) {
          var str = [];
          for(var p in obj)
          str.push(encodeURIComponent(p) + "=" + encodeURIComponent(obj[p]));
          return str.join("&amp;");
      }
  </code></pre>
  
  <p>I know this code is change the serialization algorithm and post the data with the content-type, "application/x-www-form-urlencoded". But i dont know what is syntax of it . What is <code>obj</code> in function . Please explain for me . Thank</p>