trap of in_array in php

trap of php in_array function

$array = array('testing',0,'name');
var_dump($array);

// NOTICE: this will return true
var_dump(in_array('foo', $array));

// NOTICE: this will return false
var_dump(in_array('foo', $array, TRUE));

References

1. http://cn.php.net/manual/en/function.in-array.php