shift73k/assets_old/node_modules/htmlparser2/README.md

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# htmlparser2
[![NPM version](http://img.shields.io/npm/v/htmlparser2.svg?style=flat)](https://npmjs.org/package/htmlparser2)
[![Downloads](https://img.shields.io/npm/dm/htmlparser2.svg?style=flat)](https://npmjs.org/package/htmlparser2)
[![Build Status](http://img.shields.io/travis/fb55/htmlparser2/master.svg?style=flat)](http://travis-ci.org/fb55/htmlparser2)
[![Coverage](http://img.shields.io/coveralls/fb55/htmlparser2.svg?style=flat)](https://coveralls.io/r/fb55/htmlparser2)
A forgiving HTML/XML/RSS parser. The parser can handle streams and provides a callback interface.
## Installation
npm install htmlparser2
A live demo of htmlparser2 is available [here](https://astexplorer.net/#/2AmVrGuGVJ).
## Usage
```javascript
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?!");
}
}
}, {decodeEntities: true});
parser.write("Xyz <script type='text/javascript'>var foo = '<<bar>>';</ script>");
parser.end();
```
Output (simplified):
```
--> Xyz
JS! Hooray!
--> var foo = '<<bar>>';
That's it?!
```
## Documentation
Read more about the parser and its options in the [wiki](https://github.com/fb55/htmlparser2/wiki/Parser-options).
## 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`](https://github.com/fb55/DomUtils) helper.
The `DomHandler`, while still bundled with this module, was moved to its [own module](https://github.com/fb55/domhandler). Have a look at it for further information.
## Parsing RSS/RDF/Atom Feeds
```javascript
new htmlparser.FeedHandler(function(<error> error, <object> feed){
...
});
```
Note: While the provided feed handler works for most feeds, you might want to use [danmactough/node-feedparser](https://github.com/danmactough/node-feedparser), which is much better tested and actively maintained.
## Performance
After having some artificial benchmarks for some time, __@AndreasMadsen__ published his [`htmlparser-benchmark`](https://github.com/AndreasMadsen/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](https://travis-ci.org/AndreasMadsen/htmlparser-benchmark/builds/10805007) (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 does this module differ from [node-htmlparser](https://github.com/tautologistics/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](https://github.com/substack/node-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](https://github.com/isaacs/sax-js) (originally targeted at [readabilitySAX](https://github.com/fb55/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`, your code should work as expected.