Common utility methods of jQuery

jQuery provides several inbuilt utility methods. These utility methods uses $.namespace and they are very useful and handy for your routine programming tasks. I have put together some common jQuery Utility methods to make your programming routine easy and can save your valuable time.

• $.isArray(Object): Returns true if the object is an array.
  

  //Code Starts var arrFirst = [50, 22, 10, 19, 22, 10]; var isArray = $.isArray(arrFirst); //Code Ends 

• $.isEmptyObject(Object): Returns true if the object doesn’t define any methods or properties.
  

  //Code Starts var arrFirst = [50, 22, 10, 19, 22, 10]; var isObject = $.isEmptyObject(arrFirst); //In this case, isObject will be false. //Code Ends 

• $.isFunction(Object): Returns true if the object is a function.
  

  //Code Starts function myFunc() {   //function code } var isFunction = $.isFunction(myFunc); //Code Ends 

• $.isNumeric(Object): Returns true if the object is a number.
  

  //Code Starts var num = 1; var isNumeric = $.isNumeric(num); //Code Ends 

  Read "jQuery.isNumeric in jQuery 1.7"
  
  
• $.isWindow(Object): Returns true if the object is a Window. This method accepts an argument and determines whether the argument is a window. This is used in a number of places in jQuery to determine if we're operating against a browser window (such as the current window or an iframe).This returns true is object is window, otherwise false.
  

  //Code Starts $(document).ready(function(){    alert($.isWindow(window));    var isFrame = $("#objFrm");    alert($.isWindow(isFrame)); }); //Code Ends 

  Here objFrm is defined as an iframe.
  
• $.isXMLDoc(Object): Returns true if the object is an XML document. Check to see if a DOM node is within an XML document (or is an XML document).
  

  //Code Starts $(document).ready(function(){   $.isXMLDoc(document) // false   $.isXMLDoc(document.body) // false }); //Code Ends 

• $.type(Object): Returns the built-in JavaScript type for the object.
  

  //Code Starts $(document).ready(function(){    var iVal = 12;    $.type(iVal); //number    iVal = 'jQuery';    $.type(iVal); //string }); //Code Ends 

  Below is the list of types which can be returned by this method based on the value.
  
  • boolean
  • number
  • string
  • function
  • array
  • date
  • regexp
  • null
  • undefined
  • object
• $.trim(Object): This method removes white spaces from beginning and end of the string.
  

  //Code Starts $(document).ready(function(){  var str = '     jquery by example       ';     str = $.trim(str); }); //Code Ends 

Please bookmark this article and make a practice to use these method as they can save your time.

Feel free to contact me for any help related to jQuery, I will gladly help you.