<?php

define(
	"REGEXP_PHONE_NL",
    "/(^\+[0-9]{2}|^\+[0-9]{2}\(0\)|^\(\+[0-9]{2}\)\(0\)|^00[0-9]{2}|^0)([0-9]{9}$|[0-9\-\s]{10}$)/");

$string = "+316123456789"; //based on solution given in http://stackoverflow.com/questions/17949757/regular-expression-for-dutch-phone-number

echo(
	filter_var(
		$string, 
		FILTER_VALIDATE_REGEXP,
		array(
			"options" => array ("regexp" => REGEXP_PHONE_NL)
		)
	)
);