www.pudn.com > multiple-file-upload.zip > jquery.MetaData.js, change:2009-04-08,size:3951b


/*�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: jquery.MetaData.js 16 2009-04-08 11:20:56Z diego.alto $ 
 * 
 */ 
 
/** 
 * 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);