Validating US phone number with php/regex

Question

EDIT: I\'ve mixed and modified two of the answers given below to form the full function which now does what I had wanted and then some... So I figured I

Answer 1

Alternatively, you could use some pretty simple and straightforward JavaScript to force the user to enter in a much more specified format. The Masked Input Plugin ( http://digitalbush.com/projects/masked-input-plugin/ ) for jQuery allows you to mask an HTML input as a telephone number, only allowing the person to enter a number in the format xxx-xxx-xxxx. It doesn't solve your extension issues, but it does provide for a much cleaner user experience.