Features of Jquery

Features of Jquery 
1. One can easily provide effects and can do animations. 
2. Applying / Changing CSS. 
3. Cool plugins. 
4. Ajax support 
5. DOM selection events 
6. Event Handling 


and many more other feature provide by jquery.

difference between e.preventDefault(); and return false

The difference is that preventDefault will only prevent the default event action to occur, i.e. a page redirect on a link click, a form submission, etc. and return false will also stop the event flow.

Attach data of any type to DOM elements in Jquery.

The .data() method allows us to attach data of any type to DOM elements in a way that is safe from circular references and therefore from memory leaks.

$( "div" ).data( "foo", 52 );



$( "div" ).data( "bar", { myType: "test", count: 40 } );



$( "div" ).data( { baz: [ 1, 2, 3 ] } );



$( "div" ).data( "foo" ); // 52



$( "div" ).data(); // { foo: 52,                    //   bar:{ myType: "test", count: 40 },                   //    baz: [ 1, 2, 3 ] }

Example:




<body>




 <div>



  The values stored were



  <span></span>



  and



  <span></span>



</div>



 



<script>



$( "div" ).data( "test", { first: 16, last: "pizza!" } );



$( "span:first" ).text( $( "div" ).data( "test" ).first );



$( "span:last" ).text( $( "div" ).data( "test" ).last );



</script>



 </body>




Output:The values stored were 16 and pizza!

How to create Widget in JQUERY..

(function ($) {

    $.widget('AZ.azAddNewDiscussion', $.AZ.Node, {
        options: {
          data: null      
        },
        widgetEventPrefix: $.AZ.Node.prototype.widgetEventPrefix,

        _create: function () {               // create event
            this._addNewDiscussion();

            this._on(this.element, {
                'click': function (event) {              
                },
                'click #newDiscussionNode': function (event) {
                    alert('button click');
                }

            });
        },
        _addNewDiscussion: function () {
     
          var buttonElemet = $("<h6 id='newDiscussionNode' style='text-align: right;color: #FFFFFF;margin-right: 1em;'>New Discussion</h6>");
          $(this.element).append(buttonElemet);

        }

    });

})(jQuery);

How to add and remove attribute in JQuery..

Html tag :-
<button type='submit' class='leftArrow' id='btnPost' disabled='disabled'>Post</button>

Remove attribute in jquery--
 $('#btnPost').removeAttr("disabled");

Add attribute in jquery--
 $('#btnPost').attr("disabled", "disabled");