Telephone Regular Expression

[Ell20]

Hi,

 

Im attempting to make a regular expression to check that the data input is a valid telephone number.

 

Im looking to accept telephone numbers in either of these formats:

 

+447973886123

or

+4407973886123

or

07973886123

 

I have had ago but dont think its working correctly:

 

 

if (eregi ("[a-z0-9\+]{11,14}", stripslashes(trim($_POST['contact_number'])))) {

 

 

Appreciate any help

[thebadbad]

I know why it isn't working: If you enter a number that's, say, too long, eregi will still return true, because it found a number sequence between 11 and 14 in length (i.e. it doesn't care about the rest of the input).

I don't know too much about RegEx, but I found a working solution. You just compare the length of the input with the length of the matched number; if they are equal, the input is valid, else invalid.

 

<?php
eregi('(\+?[0-9]{11,13})', stripslashes(trim($_POST['contact_number'])), $regs);
if (strlen(stripslashes(trim($_POST['contact_number']))) == strlen(trim($regs[1]))) {
	echo 'The number is valid!';
} else {
	echo 'The number is invalid.';
}
?>

 

I removed the a-z from the pattern, and added the optional plus at the start (question mark means 0 or 1 of the previous character; the escaped plus). And the max length of numbers is now 13, because I left out the plus. You should also remember that special characters inside square brackets mustn't be escaped, as they are matched literally.

[Ell20]

Seems to be working!

 

Thanks alot for your help!

 

Cheers