Updated to v2.1 from the plugin site and fixed a potential bug.

META.json

@@ -17,7 +17,7 @@
 	},
 	"provides": {
 		"jQuery.Metadata": {
-			"version": 2.0,
+			"version": 2.1,
 			"file": "jquery.metadata.js"
 		}
 	},

jquery.metadata.js

@@ -1,26 +1,30 @@
 /*
  * Metadata - jQuery plugin for parsing metadata from elements
  *
- * Copyright (c) 2006 John Resig, Yehuda Katz, Jörn Zaefferer, Paul McLanahan
+ * 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
  *
+ * Version: 2.1 
+ *
  */
 
 /**
  * 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:
+ * There are four 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.
+ * 
+ *   html5: Values are stored in data-* attributes.
  *          
  * The metadata for an element is loaded the first time the element is accessed via jQuery.
  *
@@ -29,21 +33,26 @@
  * 
  * @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"
+ * @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' 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"
+ * @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
  * 
+ * @example <p id='one' class='some_class' data-item_id='1' data-item_label='Label'>This is a p</p>
+ * @before $.metadata.setType('html5')
+ * @after $('#one').metadata().item_id == 1; $('#one').metadata().item_label == 'Label'
+ * @desc Reads metadata from a series of data-* attributes
+ *
  * @param String type The encoding type
  * @param String name The name of the attribute to be used to get metadata (optional)
  * @cat Plugins/Metadata
@@ -52,69 +61,108 @@
  * @see metadata()
  */
 
-(function($) {
+(function($, window, undefined) {
+
+	$.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), 
+					object = {}, data, match, attr;
+
+				// check for empty string in single property
+				if ( !settings.single.length ) {
+					settings.single = 'metadata';
+				}
+
+				// returned cached data if it already exists
+				data = $.data(elem, settings.single);
+				if(data) { return data; }
+
+				data = '{}';
+
+				function getData(data) {
+					if('string' !== typeof data) {
+						return data;
+					}
 
-$.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 = eval('(' + data + ')');
+					}
+				}
+
+				function getObject(data) {
+					if('string' === typeof data) {
+						data = eval('(' + data + ')');
+					}
+
+					return data;
+				}
+
+				if(settings.type == 'html5') {
+					$( elem.attributes ).each(function() {
+						var name = this.nodeName;
+
+						if(name.match(/^data-/)) {
+							name = name.replace(/^data-/, '');
+							object[name] = getObject( this.nodeValue );
+						}
+					});
+				} 
+				else {
+					if(settings.type == 'class') {
+						match = settings.cre.exec( elem.className );
+						if(match) {
+							data = match[1];
+						}
+					} 
+					else if(settings.type == 'elem') {
+						if(!elem.getElementsByTagName) { return; }
+
+						match = elem.getElementsByTagName( settings.name );
+						if(match.length) {
+							data = $.trim(match[0].innerHTML);
+						}
+					} 
+					else if(undefined !== elem.getAttribute) {
+						attr = elem.getAttribute( settings.name );
+						if(attr) {
+							data = attr;
+						}
+					}
+
+					object = getObject(data.indexOf('{') < 0 ? '{' + data + '}' : data);
+				}
+
+				if(data !== '{}') {
+					$.data( elem, settings.single, object );
+				}
+
+				return object;
 			}
-
-			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 );
-};
+	/**
+	 * 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);
+})(jQuery, this);