This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

DOMParser can parse XML or HTML source stored in a string into a DOM Document. DOMParser is specified in DOM Parsing and Serialization.

Note that XMLHttpRequest supports parsing XML and HTML from URL-addressable resources.

Creating a DOMParser

To create a DOMParser object simply use new DOMParser().

For more information about creating a DOMParser in Firefox extensions, please see the documentation for nsIDOMParser.

Parsing XML

Once you have created a parser object, you can parse XML from a string using the parseFromString method:

var parser = new DOMParser();
var doc = parser.parseFromString(stringContainingXMLSource, "application/xml");

Error handling

Note that if the parsing process failed, the DOMParser does not throw an exception, but instead returns an error document:

<parsererror xmlns="http://www.mozilla.org/newlayout/xml/parsererror.xml">
(error description)
<sourcetext>(a snippet of the source XML)</sourcetext>
</parsererror>

The parsing errors are also reported to the Error Console, with the document URI (see below) as the source of the error.

Parsing an SVG or HTML document

The DOMParser can also be used to parse a SVG document (Firefox 10.0 / Thunderbird 10.0 / SeaMonkey 2.7) or a HTML document (Firefox 12.0 / Thunderbird 12.0 / SeaMonkey 2.9). There are three different results possible, selected by the MIME type given. If the MIME type is text/xml, the resulting object will be an XMLDocument, if the MIME type is image/svg+xml, it will be an SVGDocument and if the MIME type is text/html, it will be an HTMLDocument.

var parser = new DOMParser();
var doc = parser.parseFromString(stringContainingXMLSource, "application/xml");
// returns a Document, but not a SVGDocument nor a HTMLDocument

parser = new DOMParser();
doc = parser.parseFromString(stringContainingSVGSource, "image/svg+xml");
// returns a SVGDocument, which also is a Document.

parser = new DOMParser();
doc = parser.parseFromString(stringContainingHTMLSource, "text/html");
// returns a HTMLDocument, which also is a Document.

DOMParser HTML extension for other browsers

/*
 * DOMParser HTML extension
 * 2012-09-04
 * 
 * By Eli Grey, http://eligrey.com
 * Public domain.
 * NO WARRANTY EXPRESSED OR IMPLIED. USE AT YOUR OWN RISK.
 */

/*! @source https://gist.github.com/1129031 */
/*global document, DOMParser*/

(function(DOMParser) {
	"use strict";

	var proto = DOMParser.prototype, 
        nativeParse = proto.parseFromString;

	// Firefox/Opera/IE throw errors on unsupported types
	try {
		// WebKit returns null on unsupported types
		if ((new DOMParser()).parseFromString("", "text/html")) {
			// text/html parsing is natively supported
			return;
		}
	} catch (ex) {}

	proto.parseFromString = function(markup, type) {
		if (/^\s*text\/html\s*(?:;|$)/i.test(type)) {
			var
			  doc = document.implementation.createHTMLDocument("")
			;
	      		if (markup.toLowerCase().indexOf('<!doctype') > -1) {
        			doc.documentElement.innerHTML = markup;
      			}
      			else {
        			doc.body.innerHTML = markup;
      			}
			return doc;
		} else {
			return nativeParse.apply(this, arguments);
		}
	};
}(DOMParser));

DOMParser from Chrome/JSM/XPCOM/Privileged Scope

See article here: nsIDOMParser

Specifications

Specification Status Comment
DOM Parsing and Serialization
The definition of 'DOMParser' in that specification.
Working Draft Initial definition

Browser compatibility

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
XML support 1 (Yes) 1.0 (1.7 or earlier) 9 8 3.2
SVG support 4 (Yes) 10.0 (10.0) 10 15 3.2
HTML support 30 (Yes) 12.0 (12.0) 10 17 7.1
Feature Android Edge Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
XML support (Yes) (Yes) (Yes) ? (Yes) ?
SVG support ? (Yes) 10.0 (10.0) ? ? ?
HTML support ? (Yes) 12.0 (12.0) ? ? ?

See also