html标记内的JavaScript函数调用

Question

As i understand when we invoke a method this contains reference to object which invoke this method. But what is an "object" and a "method" in the following case:

Consider html code snippet

<div id="parent">
    <input type="submit" id="submit" value="submit" onclick="doThis(this)"/>
</div>

where doThis() is JS function, such that

doThis(obj){
    obj.style.background="#ff00ff"
}

I know, that this will be contained reference to submit button, but i dont understand why.

Answer 1

See the HTML 5 specification :

When an event handler content attribute is set

...

create a function object (as defined in ECMAScript edition 5 section 13.2 Creating Function Objects)

...

Set the corresponding event handler to the aforementioned function

and

Process the Event object E as follows:

...

Invoke callback with one argument, the value of which is the Event object E , with the callback this value set to E 's currentTarget.