mbparvezme/Twitter_Username_Regex.php

## Twitter_Username_Regex.php
$testUsername = "webdevronsocial";

$regEx = '/^@?([a-zA-Z0-9_]{1,15})$/';

if( preg_match( $regEx, $testUsername ) ){
    /* This is valid, play your code here */
}
	$testUsername = "webdevronsocial";

	$regEx = '/^@?([a-zA-Z0-9_]{1,15})$/';

	if( preg_match( $regEx, $testUsername ) ){
	/* This is valid, play your code here */
	}