Javascript "this" variable confusion
- by Assaf M
Hi
I am currently reading the book "Javascript: The Good Parts" and was playing with Functions.
I produced a test script to test some properties and I am somewhat confused by the results.
Here is the code:
<h3>Object</h3>
<div style="padding-left: 10px;">
<script type="text/javascript">
function outterF()
{
document.writeln("outterF.this = " + this + "<br>");
function innerF()
{
document.writeln("innerF.this = " + this + "<br>");
return this;
};
var inner = innerF();
return this;
}
document.writeln("<b>From Inside:</b><br>");
var outF = outterF();
var inF = outF.inner;
document.writeln("<br>");
document.writeln("<b>From Outside:</b><br>");
document.writeln("outterF.this = " + outF + "<br>");
document.writeln("innerF.this = " + inF + "<br>");
</script>
</div>
Result is:
Object
From Inside:
outterF.this = [object Window]
innerF.this = [object Window]
From Outside:
outterF.this = [object Window]
innerF.this = undefined
Notice that outF.inner returns "undefined", is that some kind of a language bug?
Obviously, outF.inner points to Window object that has nothing to do with my object but shouldn't it be at least pointing to a Function object instead?
Thanks
-Assaf
