How to make one variable = two others instead of just one

Question

I posted this before and got a few answers that haven't worked for me so far. Therefore I'm going to post part of my code so you can see what I'm talking about. The highlighted part is what I pulled from another post and it's not working for me right now. I'm using visual studio 2008 and the program was written in Basic. I pulled most of this program from the net and started tweaking it to my needs, if you can help I appreciate it! Thanks! If you're familiar with arabic you will understand the letters, if not, just use A and B for the variables.

Public Class Form1
Private Sub TextBox1_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles TextBox1.TextChanged
    If CheckBox1.Checked = True Then
        TextBox2.Text = convert(TextBox1.Text)
    End If
End Sub
Private Sub OpenToolStripMenuItem_Click_1(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles OpenToolStripMenuItem.Click
    Dim AllText, LineOfText As String

    OpenFileDialog1.Filter = "Text files (*.txt)|*.txt"
    OpenFileDialog1.ShowDialog()
    If OpenFileDialog1.FileName <> "" Then
        Try '
            FileOpen(1, OpenFileDialog1.FileName, OpenMode.Input)
            Do Until EOF(1) '
                LineOfText = LineInput(1)
                AllText = AllText & LineOfText & vbCrLf
            Loop
            TextBox1.Text = AllText
            TextBox1.Select(1, 0)
            TextBox1.Enabled = True
        Catch
            MsgBox("Error opening file.")
        Finally
            FileClose(1)
        End Try
    End If
End Sub
Public Function convert(ByVal gaby As String)
    Try
        gaby = Replace(gaby.ToLower, "a", "ا")
        gaby = Replace(gaby.ToLower, "ab", "اب")
        gaby = Replace(gaby.ToLower, "ac", "اث")
        gaby = Replace(gaby.ToLower, "b", "ب")
        gaby = Replace(gaby.ToLower, "t", "ت")
        gaby = Replace(gaby.ToLower, "c", "ث")
        gaby = Replace(gaby.ToLower, "j", "ج")
        gaby = Replace(gaby.ToLower, "h", "ح")
        gaby = Replace(gaby.ToLower, "o", "خ")
        gaby = Replace(gaby.ToLower, "d", "د")
        gaby = Replace(gaby.ToLower, "z", "ذ")
        gaby = Replace(gaby.ToLower, "r", "ر")
        gaby = Replace(gaby, Chr(59), "ز")
        gaby = Replace(gaby.ToLower, "s", "س")
        gaby = Replace(gaby.ToLower, Chr(58), "ش")
        gaby = Replace(gaby.ToLower, "x", "ص")
        gaby = Replace(gaby.ToLower, "v", "ض")
        gaby = Replace(gaby.ToLower, "u", "ط")
        gaby = Replace(gaby.ToLower, "y", "ظ")
        gaby = Replace(gaby.ToLower, """", "ع")
        gaby = Replace(gaby.ToLower, "g", "غ")
        gaby = Replace(gaby.ToLower, "f", "ف")
        gaby = Replace(gaby.ToLower, "q", "ق")
        gaby = Replace(gaby.ToLower, "k", "ك")
        gaby = Replace(gaby.ToLower, "l", "ل")
        gaby = Replace(gaby.ToLower, "m", "م")
        gaby = Replace(gaby.ToLower, "n", "ن")

        ***gaby = Replace(gaby.ToLower, Chr(63), "ه", 1, Len(gaby) - 1)
        If Microsoft.VisualBasic.Right(gaby, 1) = Chr(63) Then
            Mid$(gaby, Len(gaby), 1) = "ة"
        End If***




        gaby = Replace(gaby.ToLower, "w", "و")
        gaby = Replace(gaby.ToLower, "i", "ي")
        gaby = Replace(gaby.ToLower, "e", "ء")
        gaby = Replace(gaby.ToLower, "", "")

    Catch
        MsgBox("error converting")
    End Try
    Return gaby

End Function
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click

    TextBox2.Text = convert(TextBox1.Text)

End Sub
Private Sub AboutToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles AboutToolStripMenuItem.Click
    MsgBox("سلام converter copyrights 2009" & vbCrLf & "تستمتع" & vbCrLf & "" & vbCrLf & "Hope this helps!!!")
End Sub
Private Sub AutoConvertToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles AutoConvertToolStripMenuItem.Click
    If CheckBox1.Checked = True Then
        CheckBox1.Checked = False
    Else : CheckBox1.Checked = True
    End If
End Sub
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
    TextBox1.Text = String.Empty
    TextBox2.Text = String.Empty
End Sub
Private Sub SaveToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles SaveToolStripMenuItem.Click
    SaveFileDialog1.Filter = "Text files (*.txt)|*.txt"
    SaveFileDialog1.ShowDialog()
    If SaveFileDialog1.FileName <> "" Then
        FileOpen(1, SaveFileDialog1.FileName, OpenMode.Output)
        PrintLine(1, TextBox2.Text)
        FileClose(1)
    End If
End Sub
Private Sub ExitToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ExitToolStripMenuItem.Click
    End
End Sub
End Class

Answer 1

As I read in your other post the char changes to a different value if it's at the end of the string. You could use a two dimensional array to store the original arabic character and the two different latin characters; then, for each character in your arabic string, look for it in the array and change it for the first equivalent latin character; if it's the last character in your original string then change it for the second latin character.

Answer 2

The Replace method takes a string for the portion to be replaced, not just a character. How about something like

gaby = Replace(gaby.ToLower, "1" + Chr(63), "ة" + Chr(63))
gaby = Replace(gaby.ToLower, "1", "ه")

Of course, the order of the replacements is important. The 1s that are followed by Chr(63) will be removed before the remaining 1s are replaced.

(Do I have the order in the result string wrong. The result should be right to left. Shouldn't it?)