PHP uses the strstr () function to stop spam comments.

The strstr () function searches for the first occurrence of a string in another string. This function returns the rest of the string (from the matching point ). If the searched string is not found, false is returned.

Syntax: strstr (string, search)

• The string parameter, required. Specifies the string to be searched.
• Search parameter, required. Specifies the string to be searched. If this parameter is a number, search for characters that match the ASCII value of the number.

This function is case sensitive. Use stristr () to perform case-insensitive searches ().

A simple demonstration of strstr () Functions

<?phpecho strstr("Hello NowaMagic!", "NowaMagic");?>

Program running result:

NowaMagic!

Another simple example

<?php$email  = 'name@example.com';$domain = strstr($email, '@');echo $domain; // prints @example.com//$user = strstr($email, '@', true); // As of PHP 5.3.0//echo $user; // prints name?>

Program running result:

@example.com

This function can be used in many places. If you have a lot of spam comments on your website and most spam comments contain links, you can use the following tips to prevent spam comments with links.

<? Php $ content =$ _ POST ['content']; $ garbage = strstr ($ content, "<a"); if ($ garbage = false) {// database insert Code} else {echo "<script> alert ('your comments cannot contain link'); history. go (-1); </script> ";}?>

Well, that's probably the case.