The event.preventDefault() method stops the default action of an element from happening. For example, Prevents a link from following the URL.
Monthly Archives: June 2014
jQuery Difference Between prop() and Attr()
attr(): Get the value of an attribute for the first element in the set of matched elements. Whereas,.prop(): (Introduced in jQuery 1.6) Get the value of a property for the first element in the set of matched elements.
Attributes carry additional information about an HTML element and come in name=”value” pairs. Where Property is a representation of an attribute in the HTML DOM tree. once the browser parse your HTML code ,corresponding DOM node will be created which is an object thus having properties.
.attr() gives you the value of element as it was defined in the html on page load. It is always recommended to use .prop() to get values of elements which is modified via javascript/jquery , as it gives you the original value of an element’s current state.
jQuery Create Clone Of An Object
jQuery provides clone() method which performs a deep copy of the set of matched elements, meaning that it copies the matched elements as well as all of their descendant elements and text nodes.
jQuery Stop Currently-running Animation
Using jQuery “.stop()” method we can stop the currently running animation.
jQuery Disable Animation
Using jQuery property “jQuery.fx.off”, which when set to true, disables all the jQuery animation. When this is done, all animation methods will immediately set elements to their final state when called, rather than displaying an effect.
jQuery Animation
The .animate() method allows us to create animation effects on any numeric CSS property. This method changes an element from one state to another with CSS styles. The CSS property value is changed gradually, to create an animated effect.
Syntax is:
(selector).animate({styles},speed,easing,callback)
- styles: Specifies one or more CSS properties/values toanimate.
- duration: Optional. Specifies the speed of the animation.
- easing: Optional. Specifies the speed of the element in different points of the animation. Default value is “swing”.
- callback: Optional. A function to be executed after the animation completes.
Simple use of animate function is,
Hide Copy Code
$(“btnClick”).click(function(){
$(“#dvBox”).animate({height:”100px”});
});
jQuery eq() And get()
eq() returns the element as a jQuery object. This method constructs a new jQuery object from one element within that set and returns it. That means that you can use jQuery functions on it.
get() return a DOM element. The method retrieve the DOM elements matched by the jQuery object. But as it is a DOM element and it is not a jQuery-wrapped object. So jQuery functions can’t be used.
jQuery parent() And parents()
The basic difference is the parent() function travels only one level in the DOM tree, where parents() function search through the whole DOM tree.
jQuery $(‘div’) and $(”)
$(‘<div/>’) : This creates a new div element. However this is not added to DOM tree unless you don’t append it to any DOM element.
$(‘div’) : This selects all the div element present on the page.
jQuery .size() And .length
jQuery .size()
method returns number of element in the object. But it is not preferred to use the size()
method as jQuery provide .length
property and which does the same thing. But the .length
property is preferred because it does not have the overhead of a function call.