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XMLHttpRequest getResponseHeader() Method

Complete XMLHttpRequest Object Reference

Definition and Usage

The getResponseHeader() method gets a string containing a specific response header of the XMLHttpRequest object.

A response header contains file information like length, server-type, content-type, date-modified, etc.

Syntax

xmlHttp.getResponseHeader(header)

Parameter	Description
name	A string that specifies the name of the header to get. Use the getAllResponseHeaders() method to find the possible header names for the specific document.

Example

The following code outputs the "Content-Length" header in a HTML element with id="header":

Example

<html>
<body>

<span id="header"></span>

<script type="text/javascript">
xmlhttp=null;
if (window.XMLHttpRequest)
  {// code for Firefox, Mozilla, IE7, etc.
  xmlhttp=new XMLHttpRequest();
  }
else if (window.ActiveXObject)
  {// code for IE6, IE5
  xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
  }
if (xmlhttp!=null)
  {
  xmlhttp.onreadystatechange = function()
    {
    if(xmlhttp.readyState == 4)
      {
      x=xmlhttp.getResponseHeader("Content-Length");
      document.getElementById("header").innerHTML=x;
      }
    }
  xmlhttp.open("GET", "note.xml", true);
  xmlhttp.send(null);
  }
else
  {
  alert("Your browser does not support XMLHTTP.");
  }
</script>
</body>
</html>

Output:

195

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Complete XMLHttpRequest Object Reference