Yes, you do need to evaluate the input in interface objects before
attempting conversions.
What you describe is an input failure where the user failed to enter
anything into the textbox, correct?
You need to add code to trap missing/inappropriate input and force the user
to enter the correct stuff *before* you attempt any conversions or storage
in your database.

Wael,
    Do your db fields allow nulls?  Or do you want to default to zero
( or int.Max or whatever) if the Score1.Text is null.  If you want null
to become a default value then create a global function in a module or
a shared method of a utility class:

public function FixNull(str as string,int nullVal) as integer
    If str is null then
        FixNull = nullVal
    Else
         FixNull = Cint(str)
    End if
End Function

Now your code can use FixNull in place of CInt.
You may also deal with if str is not numeric but chances are you want
the exception to escape.

Cecil Howell
MCT, MCSD, MCAD.NET, MCDFSWQZ