<?php
$text="testing:this is a test";

$text="testing:this is a test";

$start=microtime(1);
for ($c=0;$c!=100000;$c++) find1($text);
$time1=microtime(1)-$start;

$start=microtime(1);
for ($c=0;$c!=100000;$c++) find2($text);
$time2=microtime(1)-$start;

echo "find1 = $time1\n";
echo "find2 = $time2\n";

function find1($text,$separator=':') {
        $after=substr($text,strpos($text,$separator)+1);
        return $after;
}

function find2($text,$separator=':') {
        $tmp=explode($separator,$text);
        return $tmp[1];
}