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#htmlparser2

A forgiving HTML/XML/RSS parser written in JS for NodeJS. The parser can handle streams (chunked data) and supports custom handlers for writing custom DOMs/output.

##Installing npm install htmlparser2

A live demo of htmlparser2 is available at http://demos.forbeslindesay.co.uk/htmlparser2/

##Usage

var htmlparser = require("htmlparser2");
var parser = new htmlparser.Parser({
	onopentag: function(name, attribs){
		if(name === "script" && attribs.type === "text/javascript"){
			console.log("JS! Hooray!");
		}
	},
	ontext: function(text){
		console.log("-->", text);
	},
	onclosetag: function(tagname){
		if(tagname === "script"){
			console.log("That's it?!");
		}
	}
});
parser.write("Xyz <script type='text/javascript'>var foo = '<<bar>>';</ script>");
parser.end();

Output (simplified):

--> Xyz 
JS! Hooray!
--> var foo = '<<bar>>';
That's it?!

Read more about the parser in the wiki.

##Get a DOM The DomHandler (known as DefaultHandler in the original htmlparser module) produces a DOM (document object model) that can be manipulated using the DomUtils helper.

The DomHandler, while still bundled with this module, was moved to its own module. Have a look at it for further information.

##Parsing RSS/RDF/Atom Feeds

new htmlparser.FeedHandler(function(<error> error, <object> feed){
    ...
});

##Performance

After having some artificial benchmarks for some time, @AndreasMadsen published his htmlparser-benchmark, which benchmarks HTML parses based on real-world websites.

At the time of writing, the latest versions of all supported parsers show the following performance characteristics on Travis CI (please note that Travis doesn't guarantee equal conditions for all tests):

gumbo-parser   : 34.9208 ms/file ± 21.4238
html-parser    : 24.8224 ms/file ± 15.8703
html5          : 419.597 ms/file ± 264.265
htmlparser     : 60.0722 ms/file ± 384.844
htmlparser2-dom: 12.0749 ms/file ± 6.49474
htmlparser2    : 7.49130 ms/file ± 5.74368
hubbub         : 30.4980 ms/file ± 16.4682
libxmljs       : 14.1338 ms/file ± 18.6541
parse5         : 22.0439 ms/file ± 15.3743
sax            : 49.6513 ms/file ± 26.6032

##How is this different from node-htmlparser? This is a fork of the htmlparser module. The main difference is that this is intended to be used only with node (it runs on other platforms using browserify). htmlparser2 was rewritten multiple times and, while it maintains an API that's compatible with htmlparser in most cases, the projects don't share any code anymore.

The parser now provides a callback interface close to sax.js (originally targeted at readabilitySAX). As a result, old handlers won't work anymore.

The DefaultHandler and the RssHandler were renamed to clarify their purpose (to DomHandler and FeedHandler). The old names are still available when requiring htmlparser2, so your code should work as expected.