firstly please review a code sample below .
<html>
<head>
<script src="http://code.jquery.com/jquery-1.9.1.js"></script>
<script type="text/javascript">
/**/
$(function(){
var baseObj=function(){
this.firstname="joe";
this.lastname="wang";
};
var childObj=function(){
this.firstname="wq";
};
var b= new baseObj();
var c = new childObj();
baseObj.call(c);
alert(c.firstname);
});
</script>
</head>
<body>
</body>
</html>
the output is "joe" instead of the "wq".
so, found the mystery the call ?
see also:
http://stackoverflow.com/questions/4166616/understanding-the-difference-between-object-create-and-new-somefunction-in-j