Are there best practices for handling character encoding and file paths in PHP scripts, especially when transitioning from ISO-8859-1 to UTF-8?

When transitioning from ISO-8859-1 to UTF-8 in PHP scripts, it is important to ensure that all character encoding is consistent throughout the application to prevent encoding issues. This includes setting the correct encoding for database connections, input/output streams, and HTML content. Additionally, file paths should be handled carefully to avoid encoding errors when reading or writing files.

// Set the default character encoding to UTF-8
mb_internal_encoding("UTF-8");

// Set the encoding for database connections
mysqli_set_charset($connection, "utf8");

// Handle file paths with UTF-8 encoding
$file_path = mb_convert_encoding($file_path, "UTF-8", "ISO-8859-1");

// Read file with UTF-8 encoding
$file_content = file_get_contents($file_path);

// Write file with UTF-8 encoding
file_put_contents($file_path, $file_content);