Something
public text v1 · immutableif (!ereg("^[0-9]\d{2}-\d{3}-\d{4}$", $telephone)):
$error = "Not a valid phone number";
endif;
//Should allow this format: 800-555-5555if (!ereg("^[0-9]\d{2}-\d{3}-\d{4}$", $telephone)):
$error = "Not a valid phone number";
endif;
//Should allow this format: 800-555-5555