How to get substring after last separator in php?

This function will return the last substring after trimming the string according to the separator passed in.

1. Code:

 <?php 
	function getSubstringAfterLastSeparator($separator, $str){
		if (!isset($str) || trim($str) == '') {
			return "";
		}
		$wordArr = explode($separator, $str);
		$number = end($wordArr);
		return $number;
	}
	$str = "Soltuts.com is providing PHP tutorials";
	$str = getSubstringAfterLastSeparator(" ",$str);
	echo($str);
    ?> 

2. Example:

Input:

"Soltuts.com is providing PHP tutorials"

Output:

tutorials