In VB.NET safmaskedtext control, when to use Xs or Us?
Here is the description from tutorial. I can't find difference because both fields are char type.
'Each SAF Masked Text field must have a mask specified for it. In this project,
two fields are being used from the customer table. The CustId field is a 10
character field so use 10 capital Us for the mask. The Name is an alphanumeric
field and is 30 characters long. Use 30 capital Xs for the mask.'