find div in html with javascript and regex

Question

I try to select html element with javascript without! jQuery...

for example my html is:

<div id="my1231">
</div>

and i want to select any first div with id started with my, and i try so:

var regex = /my(.*)/; 
var templateCode = document.match(regex)
alert(templateCode);

but nothing happend, what i do wrong? how to select div with regex, where first part of id is static, and second random?

Answer 1

How about document.querySelectorAll?

document.querySelectorAll("[id^='my']")

Just be aware of the >= IE8 support

http://caniuse.com/#search=querySelectorAll

Answer 2

If you really want to use regex to match against ids, you must first get a node list and then loop through it and check each id individually. You can then append each matching element to a new array:

var divs = document.getElementsByTagName('div');
var regex = /my(.*)/, matches = [];

for(i=0; i< divs.length; i++){
    if(regex.test(divs[i].id)){
        matches.push(divs[i]);  
    }
}

JSFiddle