[needs comments and full explaination]hindu arabic - roman numeral program.

[yeeitsneo]

soooo. i saw a working code for a hindu arabic - roman numeral converter. the thing is. i need
to fully understand the code.
so i need someone who could explain the code clearly to me. line by line as for me to fully
understand the program. newbie here.

you can add comments or just post a reply.
thaanks.

Const sMatrix As String = "I~V~X~L~C~D~M"
Private Function toroman(ByVal sDecNum As String) As String
    Text1.Text = sDecNum
    If sDecNum <> "0" And sDecNum <> vbNullString Then
        If Len(sDecNum) > 3 Then text2.Text = String(Mid(sDecNum, 1, Len(sDecNum) - 3), "M")
        If Len(sDecNum) > 2 Then text2.Text = text2.Text & GiveLetters(Mid(sDecNum, Len(sDecNum) - 2, 1), 4)
        If Len(sDecNum) > 1 Then text2.Text = text2.Text & GiveLetters(Mid(sDecNum, Len(sDecNum) - 1, 1), 2)
            text2.Text = text2.Text & GiveLetters(Mid(sDecNum, Len(sDecNum), 1), 0)
    Else: text2.Text = "No Roman value for 0"
    End If
End Function

Private Function GiveLetters(ByVal sInput As String, ByVal iArrStart As Integer) As String

    Dim sLetterArray() As String
    sLetterArray() = Split(sMatrix, "~")

    Select Case sInput
        Case 4: GiveLetters = sLetterArray(iArrStart) & sLetterArray(iArrStart + 1)
        Case 5: GiveLetters = sLetterArray(iArrStart + 1)
        Case 9: GiveLetters = sLetterArray(iArrStart) & sLetterArray(iArrStart + 2)
        Case 6 To 8: GiveLetters = sLetterArray(iArrStart + 1) & String(sInput - 5, sLetterArray(iArrStart))
        Case Else: GiveLetters = GiveLetters + String(sInput, sLetterArray(iArrStart))
    End Select
End Function

Private Sub Command1_Click()
    Dim sRoman As String

        If Val(Text1.Text) < 1 Or Val(Text1.Text) > 3999 Then
            MsgBox "Invalid Input. Please type in an integer from 0 - 3999 only!", _
                   vbExclamation

            Text1.SetFocus
            Text1.Text = ""
            Exit Sub
         Else

        sRoman = toroman(Text1.Text)
    End If
End Sub

[Ezzaral]

No one is going to explain this line by line. Make an effort yourself and ask specific questions about the portions that you are unclear on.

[yeeitsneo]

ok. so ill make it more specific. ill italicize the lines of codes i need help with. is that ok now?

Const sMatrix As String = "I~V~X~L~C~D~M"
Private Function toroman(ByVal sDecNum As String) As String
Text1.Text = sDecNum
If sDecNum <> "0" And sDecNum <> vbNullString Then
If Len(sDecNum) > 3 Then text2.Text = String(Mid(sDecNum, 1, Len(sDecNum) - 3), "M")
If Len(sDecNum) > 2 Then text2.Text = text2.Text & GiveLetters(Mid(sDecNum, Len(sDecNum) - 2, 1), 4)*
If Len(sDecNum) > 1 Then text2.Text = text2.Text & GiveLetters(Mid(sDecNum, Len(sDecNum) - 1, 1), 2)
text2.Text = text2.Text & GiveLetters(Mid(sDecNum, Len(sDecNum), 1), 0)
Else: text2.Text = "No Roman value for 0"
End If
End Function
Private Function GiveLetters(ByVal sInput As String, ByVal iArrStart As Integer) As String
Dim sLetterArray() As String
sLetterArray() = Split(sMatrix, "~")
Select Case sInput
Case 4: GiveLetters = sLetterArray(iArrStart) & sLetterArray(iArrStart + 1)
Case 5: GiveLetters = sLetterArray(iArrStart + 1)
Case 9: GiveLetters = sLetterArray(iArrStart) & sLetterArray(iArrStart + 2)
Case 6 To 8: GiveLetters = sLetterArray(iArrStart + 1) & String(sInput - 5, sLetterArray(iArrStart))
Case Else: GiveLetters = GiveLetters + String(sInput, sLetterArray(iArrStart))
End Select
End Function
Private Sub Command1_Click()
Dim sRoman As String
If Val(Text1.Text) < 1 Or Val(Text1.Text) > 3999 Then
MsgBox "Invalid Input. Please type in an integer from 0 - 3999 only!", _
vbExclamation
Text1.SetFocus
Text1.Text = ""
Exit Sub
Else
sRoman = toroman(Text1.Text)
End If
End Sub