chop(string,charlist);

<?php
str = "Hello World!";
echo "Your string is :".str."<br>";
echo "By using 'chop()' Functions is your string is: ".chop($str,"World!");
?>

Your string is :Hello World!
By using 'chop()' Functions is your string is: Hello

<?php
str = "Hello World!";
echo "Your string is :".str."<br>";
echo "By using 'chop()' Functions is your string is: ".chop($str);
?>

Your string is :Hello World!
By using 'chop()' Functions is your string is: Hello World!

<?php
str = "Hello World!\n\n";
echo "Your string is :".str."<br>";
echo "By using 'chop()' Functions is your string is: ".chop($str,"World!");
?>

Your string is :Hello World! 
By using 'chop()' Functions is your string is: Hello World!