title: Input type hidden dosent hide in form when the value is larger in php
body: <p>I am trying to setup hidden input field value to  an xml string which is obtained from an array .
  But the <code>hidden</code> field value is displayed in <code>html</code>  while when i put a normal text as value in the hidden field it works fine.</p>
  
  <pre><code>//a large sized associative array convert to xml and set as hidden field 
              $item_array=array();
              $xml=new SimpleXMLElement('&lt;OriginDestinationOption/&gt;');
              array_walk_recursive($item_array,array($xml,'addChild')); 
             echo '&lt;input type="hidden" name="return-xml" value="'.$xml-&gt;asXML();.'" /&gt;'; ?&gt;
  </code></pre>
  
  <p>But it displays the value in html form.Whats wrong with my code?</p>
  
  <p>Note:I am using codeigniter framewrok</p>