[javascript] How to get value of a div using javascript

To put it short 'value' is not an valid attribute of div. So it's absolutely correct to return undefined.

What you could do was something in the line of using one of the HTML5 attributes 'data-*'

<div id="demo" align="center"  data-value="1">

And the script would be:

var val = document.getElementById('demo').getAttribute('data-value');

This should work in most modern browsers Just remember to put your doctype as <!DOCTYPE html> to get it valid