PHP code to clear the HTML tags in the string

This article introduced PHP to clearing HTML tags from strings
There are two ways to filter all the HTML tags in a string. One is to write our own function with regular filters, and the other is to use PHP's own function strip_tags.

 
function clear_html_label($html) 
{ 
$search = array ("'<script[^>]*?>.*?</script>'si", "'<[/!]*?[^<>]*?>'si", "'([rn])[s]+'", "'&(quot|#34);'i", "'&(amp|#38);'i", "'&(lt|#60);'i", "'&(gt|#62);'i", "'&(nbsp|#160);'i", "'&(iexcl|#161);'i", "'&(cent|#162);'i", "'&(pound|#163);'i", "'&(copy|#169);'i", "'&#(d+);'e"); 
$replace = array ("", "", "1", """, "&", "<", ">", " ", chr(161), chr(162), chr(163), chr(169), "chr(1)"); 

return preg_replace($search, $replace, $html); 
} 

//Application instance

$string ='aaa<br /> <script>fdsafsa'; 
echo clear_html_label($string);//aaa fdsafsa 

//Using PHP's built-in strip_tags(); www.zzarea.com
echo strip_tags($string);//aaa fdsafsa 

Summing up,
The above two functions yield exactly the same results, a user-defined filter for all HTML functions and a built-in PHP function, but PHP's strip_tags() function is certainly much higher in terms of efficiency. At least why don't I say more.