DocumentationIntroduction
AJAX stands for Asynchronous Javascript And Xml. It allows a web form send data to the server and refresh a part of the web form without having to refresh the whole page. This happens in the background.
AJAX
Simple example
jQuery ajax() Method
The ajax() method is used to perform an AJAX (asynchronous HTTP) request.
All jQuery AJAX methods use the ajax() method. This method is mostly used
for requests where the other methods cannot be used.
The syntax is $.ajax({name:value, name:value, ... })
The parameters specifies one or more name/value pairs for the AJAX request.
Possible names/values in the table below:
| Name | Value/Description |
| async | A Boolean value indicating whether the request should be handled asynchronous or not. Default is true |
| beforeSend(xhr) | A function to run before the request is sent |
| cache | A Boolean value indicating whether the browser should cache the requested pages. Default is true |
| complete(xhr,status) | A function to run when the request is finished (after success and error functions) |
| contentType | The content type used when sending data to the server. Default is: "application/x-www-form-urlencoded" |
| context | Specifies the "this" value for all AJAX related callback functions |
| data | Specifies data to be sent to the server |
| dataFilter(data,type) | A function used to handle the raw response data of the XMLHttpRequest |
| dataType | The data type expected of the server response. |
| error(xhr,status,error) | A function to run if the request fails. |
| global | A Boolean value specifying whether or not to trigger global AJAX event handles for the request. Default is true |
| ifModified | A Boolean value specifying whether a request is only successful if the response has changed since the last request. Default is: false. |
| jsonp | A string overriding the callback function in a jsonp request |
| jsonpCallback | Specifies a name for the callback function in a jsonp request |
| password | Specifies a password to be used in an HTTP access authentication request. |
| processData | A Boolean value specifying whether or not data sent with the request should be transformed into a query string. Default is true |
| scriptCharset | Specifies the charset for the request |
| success(result,status,xhr) | A function to be run when the request succeeds |
| timeout | The local timeout (in milliseconds) for the request |
| traditional | A Boolean value specifying whether or not to use the traditional style of param serialization |
| type | Specifies the type of request. (GET or POST) |
| url | Specifies the URL to send the request to. Default is the current page |
| username | Specifies a username to be used in an HTTP access authentication request |
| xhr | A function used for creating the XMLHttpRequest object |
List of Ajax methods
| Method | Description |
| $.ajax() | Performs an async AJAX request |
| $.ajaxPrefilter() | Handle custom Ajax options or modify existing options before each request is sent and before they are processed by $.ajax() |
| $.ajaxSetup() | Sets the default values for future AJAX requests |
| $.ajaxTransport() | Creates an object that handles the actual transmission of Ajax data |
| $.get() | Loads data from a server using an AJAX HTTP GET request |
| $.getJSON() | Loads JSON-encoded data from a server using a HTTP GET request |
| $.parseJSON() | Deprecated in version 3.0, use JSON.parse() instead. Takes a well-formed JSON string and returns the resulting JavaScript value |
| $.getScript() | Loads (and executes) a JavaScript from a server using an AJAX HTTP GET request |
| $.param() | Creates a serialized representation of an array or object (can be used as URL query string for AJAX requests) |
| $.post() | Loads data from a server using an AJAX HTTP POST request |
| ajaxComplete() | Specifies a function to run when the AJAX request completes |
| ajaxError() | Specifies a function to run when the AJAX request completes with an error |
| ajaxSend() | Specifies a function to run before the AJAX request is sent |
| ajaxStart() | Specifies a function to run when the first AJAX request begins |
| ajaxStop() | Specifies a function to run when all AJAX requests have completed |
| ajaxSuccess() | Specifies a function to run when an AJAX request completes successfully |
| load() | Loads data from a server and puts the returned data into the selected element |
| serialize() | Encodes a set of form elements as a string for submission |
| serializeArray() | Encodes a set of form elements as an array of names and values |