Add An Onclick Listener With An Existing Function Using Javascript

I have an existing javascript function: function changeColor(ID){ try{ initialize(); } finally{ changeDesign(ID); } } I want to do something like

Solution 1:

Assigning an event handler via the DOM API does not modify the actual HTML (in fact, the HTML source that the browser receives is readonly).

You have to assign a function to .onclick, not a string:

for(var x=0; x<2; x++){
    document.getElementById(x).onclick = changeColor;
}

where changeColor is defined as

function changeColor(){
    var ID = this.id; // `this` refers to element the handler is bound totry{
        initialize();
    }
    finally{
        changeDesign(ID);
    }

}

I recommend to read the excellent articles about event handling on quirksmode.org.