Question

For some reason when I use preg_replace() for a input field that stores phone numbers, I can’t store it into MySQL. Can preg_replace be used for integers or can it only be used for strings?

I am trying to make it impossible to input letters into the text field.. Can someone give some insight?

$tel = $_POST['tel'];

//when I use preg_replace, it doesn’t store the value in MySQL

$tel = preg_replace($reg_num,'', $tel);

…

    $st->bindParam(6, $tel, PDO::PARAM_INT);

Answer 1

preg_replace will cast the Integer as a String, and perform the replace correctly. However, it will return a String where bindParam is expecting an Integer.

Storing a phone number as an Integer is usually ill-advised as you would lose any leading ‘0’ or any ‘+’ sign (if used for international numbers).