VB.Net help. Code included.

[Xenarchy]

I decided to teach myself vb.net. I decided to make a stupid program just to get used to the language. I'm taking a string of character codes that I want to turn back into their respectable aplha/numeric state. Now, I can go from string to code easy, but going back again I'm running into errors. I'm sure it's my logic. Anyway here is my code please help if you can.

  ' Declare Variables Used In Function
        Dim textoutput As String = txt_output.Text
        Dim jletter As String
        Dim j As Integer = 0
        Dim jlength As Integer = Len(textoutput)
        ' Clear Input Box
        If txt_input.Text <> "" Then
            txt_input.Text = ""
        End If
        ' Loop Decode Code to Text
        For j = 0 To jlength
            If ((textoutput.Substring(j) <> " ") And (textoutput.Substring(j) <> ",")) Then
                If j = jlength Then
                    jletter = textoutput.Substring(j)
                    txt_input.Text = txt_input.Text & Chr(Val(jletter))
                ElseIf textoutput.Substring(j + 1) = "" Then
                    jletter = textoutput.Substring(j)
                    txt_input.Text = txt_input.Text & Chr(Val(jletter))
                ElseIf textoutput.Substring(j + 1) = "," Then
                    jletter = textoutput.Substring(j)
                    txt_input.Text = txt_input.Text & Chr(Val(jletter))
                ElseIf textoutput.Substring(j + 2) = "," Then
                    jletter = textoutput.Substring(j)
                    j = 1 + j
                    jletter = jletter & textoutput.Substring(j)
                    txt_input.Text = txt_input.Text & Chr(Val(jletter))
                ElseIf textoutput.Substring(j + 3) = "," Then
                    jletter = jletter & textoutput.Substring(j)
                    j = 1 + j
                    jletter = jletter & textoutput.Substring(j)
                    j = 1 + j
                    jletter = jletter & textoutput.Substring(j)
                    txt_input.Text = txt_input.Text & Chr(Val(jletter))
                End If
            End If
        Next j

Also any weblinks with tutorials on string manipulation and arrays would be nice. Or any other links would be cool. My next project involves useing a timer. I'll probly post again.

Thanks for the help.

 

[enkafan]

I didn't spend too much time taking a look at your code, but the for j= 0 to jLength looks pretty suspicious to me.

First of all, if you have the string "hello" the length will be 5. You can only do substring for positions 0 to 4 (remember zero based everything). The second problem is the j + 1, 2 or 3 code too. Once again, reading past the end of the string.

Text manipulation is pretty easy and straight forward. Just look up System.String and System.Text.StringBuilder in the MSDN help.