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@cburgmer
Created June 5, 2012 20:46
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John Resig's JavasScript HTML parser with bug fixes for parsing <script> & <style>
/*
* HTML Parser By John Resig (ejohn.org)
* Original code by Erik Arvidsson, Mozilla Public License
* http://erik.eae.net/simplehtmlparser/simplehtmlparser.js
*
* // Use like so:
* HTMLParser(htmlString, {
* start: function(tag, attrs, unary) {},
* end: function(tag) {},
* chars: function(text) {},
* comment: function(text) {}
* });
*
* // or to get an XML string:
* HTMLtoXML(htmlString);
*
* // or to get an XML DOM Document
* HTMLtoDOM(htmlString);
*
* // or to inject into an existing document/DOM node
* HTMLtoDOM(htmlString, document);
* HTMLtoDOM(htmlString, document.body);
*
*/
(function(){
// Regular Expressions for parsing tags and attributes
var startTag = /^<([-A-Za-z0-9_]+)((?:\s+\w+(?:\s*=\s*(?:(?:"[^"]*")|(?:'[^']*')|[^>\s]+))?)*)\s*(\/?)>/,
endTag = /^<\/([-A-Za-z0-9_]+)[^>]*>/,
attr = /([-A-Za-z0-9_]+)(?:\s*=\s*(?:(?:"((?:\\.|[^"])*)")|(?:'((?:\\.|[^'])*)')|([^>\s]+)))?/g;
// Empty Elements - HTML 4.01
var empty = makeMap("area,base,basefont,br,col,frame,hr,img,input,isindex,link,meta,param,embed");
// Block Elements - HTML 4.01
var block = makeMap("address,applet,blockquote,button,center,dd,del,dir,div,dl,dt,fieldset,form,frameset,hr,iframe,ins,isindex,li,map,menu,noframes,noscript,object,ol,p,pre,script,table,tbody,td,tfoot,th,thead,tr,ul");
// Inline Elements - HTML 4.01
var inline = makeMap("a,abbr,acronym,applet,b,basefont,bdo,big,br,button,cite,code,del,dfn,em,font,i,iframe,img,input,ins,kbd,label,map,object,q,s,samp,script,select,small,span,strike,strong,sub,sup,textarea,tt,u,var");
// Elements that you can, intentionally, leave open
// (and which close themselves)
var closeSelf = makeMap("colgroup,dd,dt,li,options,p,td,tfoot,th,thead,tr");
// Attributes that have their values filled in disabled="disabled"
var fillAttrs = makeMap("checked,compact,declare,defer,disabled,ismap,multiple,nohref,noresize,noshade,nowrap,readonly,selected");
// Special Elements (can contain anything)
var special = makeMap("script,style");
var HTMLParser = this.HTMLParser = function( html, handler ) {
var index, chars, match, stack = [], last = html;
stack.last = function(){
return this[ this.length - 1 ];
};
while ( html ) {
chars = true;
// Make sure we're not in a script or style element
if ( !stack.last() || !special[ stack.last() ] ) {
// Comment
if ( html.indexOf("<!--") == 0 ) {
index = html.indexOf("-->");
if ( index >= 0 ) {
if ( handler.comment )
handler.comment( html.substring( 4, index ) );
html = html.substring( index + 3 );
chars = false;
}
// end tag
} else if ( html.indexOf("</") == 0 ) {
match = html.match( endTag );
if ( match ) {
html = html.substring( match[0].length );
match[0].replace( endTag, parseEndTag );
chars = false;
}
// start tag
} else if ( html.indexOf("<") == 0 ) {
match = html.match( startTag );
if ( match ) {
html = html.substring( match[0].length );
match[0].replace( startTag, parseStartTag );
chars = false;
}
}
if ( chars ) {
index = html.indexOf("<");
var text = index < 0 ? html : html.substring( 0, index );
html = index < 0 ? "" : html.substring( index );
if ( handler.chars )
handler.chars( text );
}
} else {
html = html.replace(new RegExp("^((?:.|\n)*?)<\/" + stack.last() + "[^>]*>"), function(all, text){
text = text.replace(/<!--(.*?)-->/g, "$1")
.replace(/<!\[CDATA\[(.*?)]]>/g, "$1");
if ( handler.chars )
handler.chars( text );
return "";
});
parseEndTag( "", stack.last() );
}
if ( html == last )
throw "Parse Error: " + html;
last = html;
}
// Clean up any remaining tags
parseEndTag();
function parseStartTag( tag, tagName, rest, unary ) {
tagName = tagName.toLowerCase();
if ( block[ tagName ] ) {
while ( stack.last() && inline[ stack.last() ] ) {
parseEndTag( "", stack.last() );
}
}
if ( closeSelf[ tagName ] && stack.last() == tagName ) {
parseEndTag( "", tagName );
}
unary = empty[ tagName ] || !!unary;
if ( !unary )
stack.push( tagName );
if ( handler.start ) {
var attrs = [];
rest.replace(attr, function(match, name) {
var value = arguments[2] ? arguments[2] :
arguments[3] ? arguments[3] :
arguments[4] ? arguments[4] :
fillAttrs[name] ? name : "";
attrs.push({
name: name,
value: value,
escaped: value.replace(/(^|[^\\])"/g, '$1\\\"') //"
});
});
if ( handler.start )
handler.start( tagName, attrs, unary );
}
}
function parseEndTag( tag, tagName ) {
// If no tag name is provided, clean shop
if ( !tagName )
var pos = 0;
// Find the closest opened tag of the same type
else
for ( var pos = stack.length - 1; pos >= 0; pos-- )
if ( stack[ pos ] == tagName )
break;
if ( pos >= 0 ) {
// Close all the open elements, up the stack
for ( var i = stack.length - 1; i >= pos; i-- )
if ( handler.end )
handler.end( stack[ i ] );
// Remove the open elements from the stack
stack.length = pos;
}
}
};
this.HTMLtoXML = function( html ) {
var results = "";
HTMLParser(html, {
start: function( tag, attrs, unary ) {
results += "<" + tag;
for ( var i = 0; i < attrs.length; i++ )
results += " " + attrs[i].name + '="' + attrs[i].escaped + '"';
results += (unary ? "/" : "") + ">";
if ( special[ tag ] ) {
results += '<![CDATA[';
}
},
end: function( tag ) {
if ( special[ tag ] ) {
results += ']]>';
}
results += "</" + tag + ">";
},
chars: function( text ) {
results += text;
},
comment: function( text ) {
results += "<!--" + text + "-->";
}
});
return results;
};
this.HTMLtoDOM = function( html, doc ) {
// There can be only one of these elements
var one = makeMap("html,head,body,title");
// Enforce a structure for the document
var structure = {
link: "head",
base: "head"
};
if ( !doc ) {
if ( typeof DOMDocument != "undefined" )
doc = new DOMDocument();
else if ( typeof document != "undefined" && document.implementation && document.implementation.createDocument )
doc = document.implementation.createDocument("", "", null);
else if ( typeof ActiveX != "undefined" )
doc = new ActiveXObject("Msxml.DOMDocument");
} else
doc = doc.ownerDocument ||
doc.getOwnerDocument && doc.getOwnerDocument() ||
doc;
var elems = [],
documentElement = doc.documentElement ||
doc.getDocumentElement && doc.getDocumentElement();
// If we're dealing with an empty document then we
// need to pre-populate it with the HTML document structure
if ( !documentElement && doc.createElement ) (function(){
var html = doc.createElement("html");
var head = doc.createElement("head");
head.appendChild( doc.createElement("title") );
html.appendChild( head );
html.appendChild( doc.createElement("body") );
doc.appendChild( html );
})();
// Find all the unique elements
if ( doc.getElementsByTagName )
for ( var i in one )
one[ i ] = doc.getElementsByTagName( i )[0];
// If we're working with a document, inject contents into
// the body element
var curParentNode = one.body;
HTMLParser( html, {
start: function( tagName, attrs, unary ) {
// If it's a pre-built element, then we can ignore
// its construction
if ( one[ tagName ] ) {
curParentNode = one[ tagName ];
return;
}
var elem = doc.createElement( tagName );
for ( var attr in attrs )
elem.setAttribute( attrs[ attr ].name, attrs[ attr ].value );
if ( structure[ tagName ] && typeof one[ structure[ tagName ] ] != "boolean" )
one[ structure[ tagName ] ].appendChild( elem );
else if ( curParentNode && curParentNode.appendChild )
curParentNode.appendChild( elem );
if ( !unary ) {
elems.push( elem );
curParentNode = elem;
}
},
end: function( tag ) {
elems.length -= 1;
// Init the new parentNode
curParentNode = elems[ elems.length - 1 ];
},
chars: function( text ) {
curParentNode.appendChild( doc.createTextNode( text ) );
},
comment: function( text ) {
// create comment node
}
});
return doc;
};
function makeMap(str){
var obj = {}, items = str.split(",");
for ( var i = 0; i < items.length; i++ )
obj[ items[i] ] = true;
return obj;
}
})();
@danielweck
Copy link

There is a bug in the "startTag" regexp: parsing fails with HTML5 data- attributes (or any attribute name that contains a dash '-').

The fix is trivial, replace:
\w
with:
[\w-]

The "attr" regexp is fine.

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