Trim leading letters from a string

Question

I have a list of VAT numbers. The problem is, some of them contain a two-character country ISO code in the beginning, others do not.

I need to strip those 2 letters if they exist, for example, es7782173x becomes 7782773x and 969652255801 remains the same.

Answer 1

A PHP regex to replace all letters from the beginning:

$vat = 'es7782173x';
$vat = preg_replace('/^\D+/', '', $vat);

\D matches anything that is not a digit, and replacing it with the empty string '' effectively strips it from the beginning (^ anchor). + matches 1 or more occurrences.