How does the use of functions like trim() and stripslashes() in PHP for input filtering compare to more modern methods like filter_input()?

When filtering user input in PHP, using functions like trim() and stripslashes() can help remove extra whitespace and escape characters. However, more modern methods like filter_input() provide a more robust and secure way to filter input by specifying the type of input expected and applying filters to sanitize the data.

// Using filter_input() for input filtering
$input = filter_input(INPUT_POST, 'input_field', FILTER_SANITIZE_STRING);