What is the difference between using eregi_replace and preg_replace in PHP?

The main difference between eregi_replace and preg_replace in PHP is that eregi_replace is case-insensitive, while preg_replace is case-sensitive. Therefore, if you need to perform a case-insensitive search and replace, you should use eregi_replace. However, since eregi_replace is deprecated as of PHP 5.3.0, it is recommended to use preg_replace with the 'i' modifier instead. 

// Using preg_replace with 'i' modifier to perform a case-insensitive search and replace
$string = "Hello World";
$new_string = preg_replace('/hello/i', 'Hi', $string);
echo $new_string; // Output: Hi World

Keywords

eregi_replace preg_replace PHP regular expressions string manipulation

Related Questions