What are the best practices for handling UTF-8 encoding in PHP?

When working with UTF-8 encoded strings in PHP, it is important to ensure that your code is handling the encoding correctly to avoid issues with character encoding. One of the best practices for handling UTF-8 encoding in PHP is to set the internal encoding to UTF-8 using mb_internal_encoding() function. This will ensure that all string functions in PHP work with UTF-8 encoded strings properly.

// Set internal encoding to UTF-8
mb_internal_encoding('UTF-8');

// Example usage
$text = "Hello, 你好";
echo mb_strlen($text); // Output: 9