document.getElementById(el) has no properties.

[Markus]

I'm trying to implement an onfocus and onblur background-color changing. But, as per usual, it ain't jivin'.

Here's the function

function bg(el, col)
{
  
  document.getElementById(el).style.backgroundColor = col;
  
}

and here's how it's being called

onblur="bg(this, '#000')"

Any idea why it's saying document.getEle mentById(el) has no properties?

[acoder]

document.getEle mentById() expects an ID string, so either use el.style... or pass the id to the function.

[Markus]

Cheers for that.

I did as you suggested and changed it to el.style..

:)

[hsriat]

When you pass this as an argument to a function, it refers to the owner of the function. So in case a function is contained in an HTML tag, the owner is that HTML tag (DOM element to be exact).

<[u]input[/u] onblur="bg(this, '#000')" . . . . >
   ^                |
   '----------------'

So you should have either used this.id as argument, or the better is to do el.style, as acoder said.

[Markus]

When you pass this as an argument to a function, it refers to the owner of the function. So in case a function is contained in an HTML tag, the owner is that HTML tag (DOM element to be exact).

<[u]input[/u] onblur="bg(this, '#000')" . . . . >
   ^                |
   '----------------'

So you should have either used this.id as argument, or the better is to do el.style, as acoder said.

Thanks for that elaboration there, hs. ;)

[hsriat]

Not a problem :)
I'm always ready for explaining something which I know, and as much as I know.
That's a different thing that according to this, I'm left with few things to explain.