What functions in PHP can be used to handle UTF-8 encoding and decoding effectively?

When working with UTF-8 encoding in PHP, it is important to use functions that can handle multibyte characters effectively. Two key functions for handling UTF-8 encoding and decoding are `mb_convert_encoding()` and `utf8_encode()`.

// Example of using mb_convert_encoding() to handle UTF-8 encoding
$string = "Hello, 你好";
$encoded_string = mb_convert_encoding($string, 'UTF-8');
echo $encoded_string;

// Example of using utf8_encode() to handle UTF-8 encoding
$string = "Hello, 你好";
$encoded_string = utf8_encode($string);
echo $encoded_string;