Give information regarding jQuery CSS, AJAX and Call back Functions

**Jorgea** · 13-01-2010

I am learning jQuery concept as it is required for our project which we are making on JavaScript. The website project that I am working on is going to be scripted using JavaScript and I have never learnt anything related to jQuery. I need information regarding the following concepts of jQuerry: CSS functions, AJAX functions and Call back functions.

**Reegan** · 13-01-2010

To put it into simple words, only when the Java Script animations is fully completed, the Callback function of jQuery is executed.
Following is the syntax for jQuery Callback functions:

Code:

$(selector).hide(speed,callback)

In the above syntax the parameter callback defines a function. The hide function is first completed before this callback parameter function can be executed.

**kelfro** · 13-01-2010

JQuery defines a Javascript library. It has been very useful for simplifying programming in Javascript. One of the powerful feature of JQuery is the CSS manipulation. For CSS manipulation, JQuery supports three functions:

css(name)
css(name,value)
css({properties})

All the manipulation for CSS in JQuery are performed with the help of the above mentioned three functions.

**MindSpace** · 13-01-2010

To initialize a value to the properties of CSS you may make use of the $(selector).css({properties}) function of Jquery CSS manipulation. This is done for all the matching elements. Here is an example to demonstrate the $(selector).css({properties}) function of Jquery CSS manipulation:

Code:

<html>

<head>
<script type="text/javascript" src="Jqry.js"></script>
<script type="text/javascript">
$(document).ready(function(){
  $("button").click(function(){
  $("p").css({"background-color":"White","font-size":"100%"})
  })
})
</script>
</head>

<body bgcolor= "Red">
<p>Paragraph Line</p>
<h1>Heading</h1>
<p>Second Para.</p>
<button type="button">Change</button>
</body>
</html>

**Praetor** · 13-01-2010

Asynchronous JavaScript and XML is the full form for AJAX. Its main purpose to simplify the web applications and also to make the more user friendly. To enhance the web development with AJAX technique a rich set of methods is available in J-Query. Here are a few AJAX Requests in J-Query:

post(url,data,callback,type)- Making use of the HTTP POST to load remote data.
ajax(options)- To load data in the object of XMLHttpRequest

**opaper** · 13-01-2010

For Size Manipulation in jQuery there are two finctions available:
$(selector).width(value)
$(selector).height(value)

Code:

<html>
<head>
<script type="text/javascript" src="temp.js"></script>
<script type="text/javascript">
$(document).ready(function(){
  $("button").click(function(){
  $("#D1").height("500px")
  })
})
</script>
</head>

<body>
<div id="D1" style="background:Gren;height:200px;width:150px">
jQuery</div>
<div id="D2" style="background:Green;height:200px;width:150px">
CSS</div>
<button type="button">Enter</button>
</body>

</html>

To set the width of elements that are matching the function width(value) is used and to set the height of elements that are matching the function height(value) is used.