The Apply, call method, and length property instances of JavaScript functions

<script language= "javascript" type= "Text/javascript" >
<!--
Defines a function func1, with attribute p and method a
function Func1 () {
this.p= "func1-";
This.a=function (ARG) {
alert (THIS.P+ARG);
}
}
Defines a function func2, with attribute p and method b
function Func2 () {
this.p= "func2-";
This.b=function (ARG) {
alert (THIS.P+ARG);
}
}
var obj1=new func1 ();
var obj2=new func2 ();
obj1.a ("Bya"); Show Func1-bya
obj2.b ("Byb"); Show Func2-byb
Obj1.a.apply (obj2,["bya"]); Displays Func2-bya, where ["Bya"] is an array of only one element, the same as
Obj2.b.apply (obj1,["BYB"]); Show Func1-byb
Obj1.a.call (Obj2, "bya"); Show Func2-bya
Obj2.b.call (obj1, "byb"); Show Func1-byb

-->
</script>