PHPで文字列の最後の数桁をインターセプトする方法

string substr ( string string, int start [, int length] )

$str_bh='123456789';$abc=substr($str_bh,-4);
echo $abc;

6789

<?php
echo substr("Hello world!",6,5);
?>

world

<?php
echo substr(&#39;abcdef&#39;, 1);
?>

bcdef

string strstr ( string string, string needle )

<?php
$email = &#39;user@5idev.com&#39;;
$domain = strstr($email, &#39;@&#39;);
echo $domain;
?>

@5idev.com

string strrchr ( string string, string needle )

<?php
$str="AAA|BBB|CCC";
echo strrchr($str, "|");
?>

|CCC