pattern matching question

Normally I can get the patterns to work, but this one is stumping me... and it's really obvious!

All I want is only four digits to be accepted, no more, no less than 4, and no other characters than 0-9.

So I have

$string = "1111";
$result = eregi("[0-9]{4}", $string);

but this allows more than four digits.

I've tried other variations, including using preg_match, but I'm just not quite getting it!

Anyone help?

Just need the start of line and end of line characters.

eregi("^[0-9]{4}$", $string);

thanks for that!

I was so close, yet so far!