Represents an XML request using HTTP.

Members

The XMLHttpRequest object has these types of members:

• Events
• Methods
• Properties

Events

The XMLHttpRequest object has these events.

Methods

The XMLHttpRequest object has these methods.

Properties

The XMLHttpRequest object has these properties.

Standards information

• XMLHttpRequest, Section 3

Remarks

The XMLHttpRequest property is available on the window object.

var oReq = new XMLHttpRequest;

Starting with Internet Explorer 10 in Windows 8, the responseXML property returns a native XML document. This can affect webpages written for earlier versions of Windows Internet Explorer, but makes it more compatible with other browsers.

For previous version of Internet Explorer, the additional step of passing responseText through DOMParser.

var xhr = new XMLHttpRequest();

//...

var parser = new DOMParser();

var doc = parser.parseFromString(xhr.responseText, 'text/xml');

// 'doc' contains a native document in both IE9 and IE10

With Internet Explorer 10 in Windows 8, the use of responseXML simplifies getting a native XML document.

var xhr = new XMLHttpRequest();

//...

var doc = xhr.responseXML;

// 'doc' contains a native document in IE10’s Standards and Quirks document modes

// it contains an MSHTML document in IE9 and in IE10’s compatibility document modes

For more info, see XMLHttpRequest responseXML in Internet Explorer 10.

With the XMLHttpRequest object, clients can retrieve and submit XML data directly to a web server without reloading the document. To convert XML data into renderable HTML content, use the client-side XML DOM or Extensible Stylesheet Language Transformations (XSLT) to compose HTML elements for presentation.

The native scripting object also supports the use of expandos (custom properties), and properly recognizes the 'this' notation of JavaScript.

The XMLHttpRequest property is available on the window object in Windows Internet Explorer 7.

var oReq = new XMLHttpRequest;

To support versions of Windows Internet Explorer prior to Internet Explorer 7, use the following function to get the XMLHttpRequest object.

function getXMLHttpRequest() 
{
    if (window.XMLHttpRequest) {
        return new window.XMLHttpRequest;
    }
    else {
        try {
            return new ActiveXObject("MSXML2.XMLHTTP.3.0");
        }
        catch(ex) {
            return null;
        }
    }
}

Examples

The following script demonstrates how to create and use the XMLHttpRequest object. For best client-side performance, the XMLHTTP request is asynchronous and uses an onreadystatechange event handler to process the data returned by the call. The script uses the getXMLHttpRequest() function defined above to create the request object.

function handler()
{
    if (oReq.readyState == 4 /* complete */) {
        if (oReq.status == 200) {
            console.log(oReq.responseText);
        }
    }
}
var oReq = getXMLHttpRequest();
if (oReq != null) {
    oReq.open("GET", "http://localhost/test.xml", true);
    oReq.onreadystatechange = handler;
    oReq.send();
}
else {
    window.console.log("AJAX (XMLHTTP) not supported.");
}