[Javascript] Problem w/Javascript, interpolation, functions, onclick

[Peter-Paul Koch]

> >On 10/25/06, Paul Novitski <paul at juniperwebcraft.com> wrote:
> >>                  // now act on the object whose behavior triggered
> >>this function
> >>                  var sClass = this.tagName;       // etc.
> >
> >This is incorrect. In IE, events are executed in the window scope, so
> >when you do this.tagName, it is equivalent to doing window.tagName.
> >You must get the target element from the event itself
>
>
> According to PP, Matt, what you say is true if you're inserting your
> function calls in the HTML but I'm correct if applying the behavior
> through the DOM.


In the quoted function the this keyword refers to oSomething; ie. the
element you registered the event handler on.

<tag id="something">something to click</tag>

...

        var oSomething = document.getElementById("something");
                if (!oSomething) return;
        oSomething.onclick = jsDoSomething; <-- event handler
registered on oSomething with the traditional model, in which this
works fine

...

        function jsDoSomething(evt)
        {
                // cancel event-bubbling
                        if (evt) { event = evt; }
                event.cancelBubble = true;

                // now act on the object whose behavior triggered
this function
                var sClass = this.tagName;       // etc. <-- this
refers to oSomething
        }



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