<?php

/**
 * Make email clickable
 *
 * @author Nguyen Tan Tai <taisang1996@gmail.com>
 * @param  string 	Input text
 * @param  boolean 	Want add <span> inside <a>?
 * @return string 	Replaced string format with link or link span
 */
function makeEmailClickable($input, $span = false) {
	$regex = '/\w+@\w+\.\w+/';

	$formatLink = function($matches) {
		return "<a href=\"mailto:$matches[0]\">$matches[0]</a>";
	};

	$formatLinkSpan = function($matches) {
		return "<a href=\"mailto:$matches[0]\"><span>$matches[0]</span></a>";
	};

	$format = $span ? $formatLinkSpan : $formatLink;

	return preg_replace_callback($regex, $format, $input);
}

$input = <<<EOD
taisang1996@gmail.com
ngthiminhthu121@gmail.com
taisang19962gmail.com
taisang1996#gmail.com
taisang1996\$gmail.com
taisang1996@gmail,com
taisang1996@gmail/com
taisang1996@gmail\com
taisang1996@gmail*com
01234432132
EOD;

var_dump($input);
var_dump(makeEmailClickable($input));
var_dump(makeEmailClickable($input, true));