Learning 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.