Need Help with Regular Expression - Allow empty field


I need to allow for blank lines for regular expressions.

An example of a regular expression I am using is:

^([0-9a-zA-Z!@#$%&-_=+ ]){0,25}$

This works fine except if the field is empty.

The field is not required, so no one has to enter anything.

If empty, the item can not be added to the cart, even thought it is not required.

What do I have to change in the above regedit formula to allow for an empty field.

Would also need to know what to have to allow for empty lines also.


I am using this multi-line expression


This works fine for up to 2 lines with up to 12 characters per line, but won’t work for a blank text area.

This is not set as a required option.