[VB2010 ASP.NET] codice per sostituzione caratteri

[Gregorio89]

dim chararray() as char
charArray = stringa.tochararray

For z = 0 To charArray.Length - 1
If Char.IsDigit(charArray(z)) Then
correct_Values = correct_Values & charArray(z)
ElseIf charArray(z) = "×" And z = 0 Then
correct_Values = "-Null-"
ElseIf charArray(z) = "×" And z > 0 Then
If Char.IsDigit(charArray(z - 1)) Then
correct_Values = correct_Values & "%"
Else : correct_Values = correct_Values & "-Null-"
End If
End If