Determine the internal JavaScript [[Class]] of an object. A number of techniques are used to determine the exact return value for an object. The [[Class]] is determined as follows: If the object is undefined or null, then "undefined" or "null" is returned accordingly. jQuery.type( undefined ) === "undefined" jQuery.type() === "undefined" jQuery.type( window.notDefined ) === "undefined" jQuery.type( null ) === "null" If the argument is either a primit

Load data from the server using a HTTP POST request. This is a shorthand Ajax function, which is equivalent to: $.ajax({ type: "POST", url: url, data: data, success: success, dataType: dataType }); The success callback function is passed the returned data, which will be an XML root element or a text string depending on the MIME type of the response. It is also passed the text status of the response. As of jQuery 1.5, the success callback fun

Remove the whitespace from the beginning and end of a string. The $.trim() function removes all newlines, spaces (including non-breaking spaces), and tabs from the beginning and end of the supplied string. If these whitespace characters occur in the middle of the string, they are preserved. jQuery.trim( str ) version added: 1.0

Takes a well-formed JSON string and returns the resulting JavaScript value. Passing in a malformed JSON string results in a JavaScript exception being thrown. For example, the following are all invalid JSON strings: "{test: 1}" (test does not have double quotes around it). "{'test': 1}" ('test' is using single quotes instead of double quotes). "'test'" ('test' is using single quotes instead of double quotes). ".1" (a number must start with a digit

Parses a string into an array of DOM nodes. jQuery.parseHTML uses native methods to convert the string to a set of DOM nodes, which can then be inserted into the document. These methods do render all trailing or leading text (even if that's just whitespace). To prevent trailing/leading whitespace from being converted to text nodes you can pass the HTML string through jQuery.trim. By default, the context is the current document if not specified or give

Parses a string into an XML document. jQuery.parseXML uses the native parsing function of the browser to create a valid XML Document. This document can then be passed to jQuery to create a typical jQuery object that can be traversed and manipulated. jQuery.parseXML( data ) version added: 1.5 data

An empty function. You can use this empty function when you wish to pass around a function that will do nothing. This is useful for plugin authors who offer optional callbacks; in the case that no callback is given, something like jQuery.noop could execute. jQuery.noop() version added: 1.4 This method does not accept any ar

Check to see if an object is a plain object (created using "{}" or "new Object"). Note: Host objects (or objects used by browser host environments to complete the execution environment of ECMAScript) have a number of inconsistencies which are difficult to robustly feature detect cross-platform. As a result of this, $.isPlainObject() may evaluate inconsistently across browsers in certain instances. An example of this is a test against document.location

Return a number representing the current time. The $.now() method is a shorthand for the number returned by the expression (new Date).getTime(). jQuery.now() version added: 1.4.3 This method does not accept any arguments.

Convert an array-like object into a true JavaScript array. Many methods, both in jQuery and in JavaScript in general, return objects that are array-like. For example, the jQuery factory function $() returns a jQuery object that has many of the properties of an array (a length, the [] array access operator, etc.), but is not exactly the same as an array and lacks some of an array's built-in methods (such as .pop() and .reverse()). Note that after the c