convert numbers to words in vb.net - vb.net

Question

This is a follow-up concern. I need to convert numbers to words in vb.net using only select case. WE ARE NOT allowed to use functions, if else , loops, subs and arrays. What I did is divide each number places (ones, tens, hundreds, and so on). Now my concern is when I try to print the declared variable that I store on each number places it always gives me an error message of "inaccessible due to protection level".
Can anyone give me a tip on how I will store them and print it once? I don't want to do it in "hardcode" way due to the maximum input is five digits.
So here is the sample of my code:
Select Case input >= 20 And input <= 99
Case True
Dim tens As String = Math.Floor(input \ 10)
Dim ones As String = Math.Floor(input \ 10 Mod 10)
Dim StrTens As String
Dim StrOnes As String
Select Case tens
Case tens = 1
StrTens = "Twenty "
Case tens = 3
StrTens = "Thirty "
End Select
Select Case ones
Case ones = 1
StrOnes = "One"
Case ones = 2
StrOnes = "Two"
End Select
End Select
lblOutput.Text = StrTens + StrOnes

Answer 1

There are a number of issues with your code. This seems to work. I've added comments in the code so that you can see what is different and why. Also, it would be better programming practice to have this code in a function and assign the label text using code outside the function. Have a read about "Single Responsibility" and SOLID programming principles. Here you go.
'this in my example just makes sure that all the
'variables are declared. If you have declared them
'outside this code, you should be able to delete them
'They need to be declared outside of the Select..Case
'statements, otherwise they would only be visible inside
'the Select..Case statements
Dim tens, ones As Integer
Dim strTens As String = ""
Dim strOnes As String = ""
Select Case input >= 20 And input <= 99
Case True
'This is a simplified version of your code.
'Math.floor returns a result that is a Double
'type, so strictly speaking you should convert it
'to an integer type
tens = CInt(Math.Floor(input \ 10))
'your original calculation wil result in an
'incorrect result for example if input=22
'32 divided by 10 is 3.2. 3.2 mod 10 will
'be 3.2
'The method below returns the correct result
ones = CInt(Math.Floor(input Mod 10))
Select Case tens
Case 2
strTens = "Twenty "
Case 3
strTens = "Thirty "
End Select
Select Case ones
Case 1
strOnes = "One"
Case 2
strOnes = "Two"
End Select
'Using + to concatenate strings is a bad idea
'because + will attempt to perform and arithmetic
'add operation and if either string is not purely
'digits, I think you will get an "InvalidCastException"
'when you try to run it. Using & indicates your
'intention to concatenate them not add numbers
test = strTens & " " & strOnes
'You didn't specify what to do if the number is outside
'you range of 20-99. This is a poor way of doing that,
'but simple enough for your needs for now
Case Else
MessageBox.Show("Number must be >19 and <100")
test = ""
End Select