|
|
/*
|
|
|
* Metadata - jQuery plugin for parsing metadata from elements
|
|
|
*
|
|
|
* Copyright (c) 2006 John Resig, Yehuda Katz, J<>örn Zaefferer, Paul McLanahan
|
|
|
*
|
|
|
* Dual licensed under the MIT and GPL licenses:
|
|
|
* http://www.opensource.org/licenses/mit-license.php
|
|
|
* http://www.gnu.org/licenses/gpl.html
|
|
|
*
|
|
|
* Revision: $Id$
|
|
|
*
|
|
|
*/
|
|
|
|
|
|
/**
|
|
|
* Sets the type of metadata to use. Metadata is encoded in JSON, and each property
|
|
|
* in the JSON will become a property of the element itself.
|
|
|
*
|
|
|
* There are three supported types of metadata storage:
|
|
|
*
|
|
|
* attr: Inside an attribute. The name parameter indicates *which* attribute.
|
|
|
*
|
|
|
* class: Inside the class attribute, wrapped in curly braces: { }
|
|
|
*
|
|
|
* elem: Inside a child element (e.g. a script tag). The
|
|
|
* name parameter indicates *which* element.
|
|
|
*
|
|
|
* The metadata for an element is loaded the first time the element is accessed via jQuery.
|
|
|
*
|
|
|
* As a result, you can define the metadata type, use $(expr) to load the metadata into the elements
|
|
|
* matched by expr, then redefine the metadata type and run another $(expr) for other elements.
|
|
|
*
|
|
|
* @name $.metadata.setType
|
|
|
*
|
|
|
* @example <p id="one" class="some_class {item_id: 1, item_label: 'Label'}">This is a p</p>
|
|
|
* @before $.metadata.setType("class")
|
|
|
* @after $("#one").metadata().item_id == 1; $("#one").metadata().item_label == "Label"
|
|
|
* @desc Reads metadata from the class attribute
|
|
|
*
|
|
|
* @example <p id="one" class="some_class" data="{item_id: 1, item_label: 'Label'}">This is a p</p>
|
|
|
* @before $.metadata.setType("attr", "data")
|
|
|
* @after $("#one").metadata().item_id == 1; $("#one").metadata().item_label == "Label"
|
|
|
* @desc Reads metadata from a "data" attribute
|
|
|
*
|
|
|
* @example <p id="one" class="some_class"><script>{item_id: 1, item_label: 'Label'}</script>This is a p</p>
|
|
|
* @before $.metadata.setType("elem", "script")
|
|
|
* @after $("#one").metadata().item_id == 1; $("#one").metadata().item_label == "Label"
|
|
|
* @desc Reads metadata from a nested script element
|
|
|
*
|
|
|
* @param String type The encoding type
|
|
|
* @param String name The name of the attribute to be used to get metadata (optional)
|
|
|
* @cat Plugins/Metadata
|
|
|
* @descr Sets the type of encoding to be used when loading metadata for the first time
|
|
|
* @type undefined
|
|
|
* @see metadata()
|
|
|
*/
|
|
|
|
|
|
(function($) {
|
|
|
|
|
|
$.extend({
|
|
|
metadata : {
|
|
|
defaults : {
|
|
|
type: 'class',
|
|
|
name: 'metadata',
|
|
|
cre: /({.*})/,
|
|
|
single: 'metadata'
|
|
|
},
|
|
|
setType: function( type, name ){
|
|
|
this.defaults.type = type;
|
|
|
this.defaults.name = name;
|
|
|
},
|
|
|
get: function( elem, opts ){
|
|
|
var settings = $.extend({},this.defaults,opts);
|
|
|
// check for empty string in single property
|
|
|
if ( !settings.single.length ) settings.single = 'metadata';
|
|
|
|
|
|
var data = $.data(elem, settings.single);
|
|
|
// returned cached data if it already exists
|
|
|
if ( data ) return data;
|
|
|
|
|
|
data = "{}";
|
|
|
|
|
|
if ( settings.type == "class" ) {
|
|
|
var m = settings.cre.exec( elem.className );
|
|
|
if ( m )
|
|
|
data = m[1];
|
|
|
} else if ( settings.type == "elem" ) {
|
|
|
if( !elem.getElementsByTagName )
|
|
|
return undefined;
|
|
|
var e = elem.getElementsByTagName(settings.name);
|
|
|
if ( e.length )
|
|
|
data = $.trim(e[0].innerHTML);
|
|
|
} else if ( elem.getAttribute != undefined ) {
|
|
|
var attr = elem.getAttribute( settings.name );
|
|
|
if ( attr )
|
|
|
data = attr;
|
|
|
}
|
|
|
|
|
|
if ( data.indexOf( '{' ) <0 )
|
|
|
data = "{" + data + "}";
|
|
|
|
|
|
data = eval("(" + data + ")");
|
|
|
|
|
|
$.data( elem, settings.single, data );
|
|
|
return data;
|
|
|
}
|
|
|
}
|
|
|
});
|
|
|
|
|
|
/**
|
|
|
* Returns the metadata object for the first member of the jQuery object.
|
|
|
*
|
|
|
* @name metadata
|
|
|
* @descr Returns element's metadata object
|
|
|
* @param Object opts An object contianing settings to override the defaults
|
|
|
* @type jQuery
|
|
|
* @cat Plugins/Metadata
|
|
|
*/
|
|
|
$.fn.metadata = function( opts ){
|
|
|
return $.metadata.get( this[0], opts );
|
|
|
};
|
|
|
|
|
|
})(jQuery); |
