title: How to send (put) "Array" values into XMLHttpRequest Object Ajax Request?
body: <p>We can send (put) single values to send into XMLHttpRequest with Ajax. But how to send "Array" element's values?</p>
  
  <p><strong>EXAMPLE#1 (Ok!)</strong><br>
  For this simple value:</p>
  
  <pre><code>&lt;input type="hidden" name="param" value="hello" /&gt;
  </code></pre>
  
  <p>We can simply put the value into XMLHttpRequest object like:</p>
  
  <pre><code>xmlhttp.open("GET","ajax.php?param="+document.getElementById("param").value,true);
  xmlhttp.send();
  </code></pre>
  
  <p>Above method is simple and ok.<br>
  But how about to send (put) "Array" values?</p>
  
  <p><strong>EXAMPLE#2 * (Problem with Array Values)</strong><br></p>
  
  <pre><code>&lt;input type="hidden" name="param[]" value="hello" /&gt;
  &lt;input type="hidden" name="param[]" value="world" /&gt;
  ...
  xmlhttp.open("GET","ajax.php?params="+document.getElementById("param").value,true);
  </code></pre>
  
  <p><br>Note: Server side will be with PHP.</p>