PHP extract multiple emails from text

<?php
/*

Name : PHP extract multiple emails from text

Function expects one parameter which is the text from which email addresses are to be extracted.

It outputs email ids as comma separated list.

*/

function extractMultipleEmailsFromText($text){
    // Define the regular expression from extracting email addresses
    $regexp = '/([a-z0-9_\.\-])+\@(([a-z0-9\-])+\.)+([a-z0-9]{2,4})+/i';
	
	// Now use it to actually extract email addresses to array
    preg_match_all($regexp, $text, $m);
	
	// Now convert it into comma separated list of email addresses
	$email_addresses=implode( ", ",$m[0]);
	
	// Now return the list of extracted email addresses
	return $email_addresses;
	
	
} // End of Exctract Multiple Emails From Text function




// Let us write some dummy text to test  it
$test_string = 'Let us put some text here

test1@mysite.com

and some other text 

what1@where.com


and then test8@nothing.org 
';

//Lets have fun and echo the result to see if it works!
echo extractMultipleEmailsFromText($test_string);

?>