get text javascript + iframe

Question

i have html code

site index.html

<html>
<body>
  <iframe id="html2" frameborder="0" src="html2.htm" marginwidth="0" marginheight="0" style="height: 492px;"></iframe>
</body>
</html>

site html2.htm

<html>
<body>
  <div><p id='123'>hello</p></div>
</body>
</html>

when i using document.getElementById('123') in site index.html return = null; how i can get it

possible duplicate: http://stackoverflow.com/questions/1088544/javascript-get-element-from-within-an-iframe Also, id cannot start with a number and this will not work at all if the iframed page is in a different domain. — ElGavilan, Dec 15 '13 at 07:28
Greeting new user. Come with me in the backstreet. I'll show you a little trick : http://stackoverflow.com/tour — Milche Patern, Dec 15 '13 at 07:30

score 0 · Answer 1 · answered Dec 15 '13 at 08:11

You need to first access innerDoc of iframe by:

var iframe = document.getElementById('html2');
var innerDoc = iframe.contentDocument || iframe.contentWindow.document;

once you get the object, now you can access:

innerDoc.getElementById('divId');

For ID in html, you need to follow these rules:

ID should match:

[A-Za-z][-A-Za-z0-9_:.]*

but one should avoid : and . beacause jQuery selector conflict on these with class and filter.

1 Answers1