Simple, ..yet doesn't work

**toptomato** · 08-23-2012, 09:07 AM

just wondering why my syntax isn't working here..

this doesn't work...

PHP Code:


function setBg() {

el = document.getElementsByTagName('body');

el.style.backgroundColor = "#f9f363";

}

but this does.....

PHP Code:


function setBg() {

document.body.style.backgroundColor = "#f9f363";

}

**bionoid** · 08-23-2012, 09:16 AM

getElementsByTagName returns a collection, so this should work:

Code:

function setBg() { 
el = document.getElementsByTagName('body')[0]; 
el.style.backgroundColor = "#f9f363"; 
}

**JMRKER** · 08-23-2012, 09:24 AM

Originally Posted by toptomato

just wondering why my syntax isn't working here..

this doesn't work...

PHP Code:


function setBg() {

el = document.getElementsByTagName('body');

el.style.backgroundColor = "#f9f363";

}

but this does.....

PHP Code:


function setBg() {

document.body.style.backgroundColor = "#f9f363";

}

getElementsByTagName() returns an array, not an individual value.
Needs to be accessed like an array element.
See:

Code:

<script type="text/javascript">
function setBG() {
  el = document.getElementsByTagName('body');
  el[0].style.backgroundColor = "#00f363";
} 

function SETbg() {
  document.body.style.backgroundColor = "#f9f363";
} 
</script>
<body>
<button onclick="setBG()">Tag BG set</button>
<button onclick="SETbg()">DOM BG set</button>
</body>