c# - i want int in my textbox and in my other i want string with "if" -

i'm new using c#

so in textbox postal code. want can use int (1,2,3,4,...) , may 4 numbers. how can that?

and happens when need fill in birthday?

and happens when fill in email? (test47@hotmail.com)

so next question is: in textbox name, want can use string (paul, tom, ...). how can that?

it must "if". not try & catch

thanks helping me!

try in xaml, use inputscope

<textbox inputscope="number" name="postalcode" />