Jquery pluign development example

(function($){

    $.fn.ChangeStyle = function(options,msg){
             
            var opts = $.extend({},$.fn.ChangeStyle.defaults, options); 
            
            this.css("background",opts.background);  
            this.css("color",opts.color); 
            
            //private method
            Note(msg);
            
            //public method
            $.fn.ChangeStyle.customAction();
            
        };
    function Note(msg)
    {
                
        if(undefined != msg)
        {
            alert(msg);
        }
    }

    $.fn.ChangeStyle.defaults = { background:"#999",color:"red"};
    
    $.fn.ChangeStyle.customAction = function(){};

})(jQuery);
 

//Invoke the pluign example
$(function()
{

 //set properties
 //$("form").ChangeStyle.defaults.background = "#f1f1f1";
 //$("form").ChangeStyle.defaults.color = "blue";

 $("form").ChangeStyle.customAction = function(){ alert("this is custom action")};
 $("form").ChangeStyle({ background:"#999",color:"red"},"hi");


});