What is the difference between setAttribute and dot notation in Javascript? [duplicate]

Question

Possible Duplicate:
When to use setAttribute vs .attribute= in JavaScript?

Why do you sometimes set an attribute like this:

x.type = "submit"; 

and other times like this:

x.setAttribute("type", "submit");

I always figured it didn't matter which way, but I'm having an issue doing this:

x.onClick = save;

but when I switch it to this it works:

x.setAttribute("onClick", "save()");

Answer 1

setAttribute only works on DOM elements and lowercases the attribute name on HTML elements. And you can't use dot notation to assign values to dynamic attribute names.

And there's also this:

Using setAttribute() to modify certain attributes, most notably value in XUL, works inconsistently, as the attribute specifies the default value. To access or modify the current values, you should use the properties. For example, use elt.value instead of elt.setAttribute('value', val).