How to check length only if not empty and if empty ignore

Question

I want to only check for length of this value if the variable is not empty and ignore checking length if the variable is empty. The following Always checks length and doesn't consider the first parameter of the if statement.

PHP

if ($Zip !== '' && (strlen($Zip) !== 4)){

Answer 1

Try this:

if (!empty($Zip) && (strlen($Zip) !== 4)){

Apply this code and remove your code. It will work.