VB.NET conversion

[Techno]

So, this code works fine in VB.NET:

Dim sModifiedAccountNumber_AsciiHex
Dim iByte As Byte = 0
Dim iIdx As Integer = 0
Dim strByte As String = String.Empty

sModifiedAccountNumber_AsciiHex = "FC13"
For iIdx = 1 To 3 Step 2

iByte = CByte("&H" & Mid$(sModifiedAccountNumber_AsciiHex, iIdx, 2))
If iByte >= 120 And iByte <= 127 Then
iByte = iByte Or &H80
strByte = Hex$(iByte)
Do While Len(strByte) < 2
strByte = "0" & strByte
Loop
Mid$(sModifiedAccountNumber_AsciiHex, iIdx, 2) = strByte
End If

Next

but, how would I convert this to C#?
I mean, I have majority of it however this always results in a format exception being thrown:

..
..
for (int iIdx = 1; iIdx <= 3; iIdx += 2)
{
iByte = byte.Parse(("&H" + modAccountNumberAsciiHex.Substring((iIdx - 1), 2)));

[jmcilhinney]

That's horrible VB.NET code and I'm guessing that it was written in VB6 originally. "&H" should never appear in a String in VB.NET. It can work but it's dodgy. It's absolutely useless in C# though, because &H is the VB-specific prefix for hexadecimal literals. The equivalent in C# is 0x, but that shouldn't appear in a String either. If you want to convert a hexadecimal String to a Byte then you can use Byte.Parse and use NumberStyles.HexNumber or else Convert.ToByte and specify the base as 16. In both cases, DO NOT add any prefix to the String.

[ThomasJohnsen]

Try omitting the "&H" as jmcilhinney suggests and add NumberStyle:

byte.Parse(s, NumberStyles.AllowHexSpecifier);

Regards Tom

[Techno]

I agree jmcilhinney you are right, it IS VB6 code....

so now this works in C#:


iByte = byte.Parse(modAccountNumberAsciiHex.Substring((iIdx - 1), 2), System.Globalization.NumberStyles.HexNumber);

[Techno]

last one:

I know Mid$ is basically substring but how can I do this in C#?

                Mid$(sModifiedAccountNumber_AsciiHex, iIdx, 2) = strByte

[jmcilhinney]

last one:

I know Mid$ is basically substring but how can I do this in C#?

                Mid$(sModifiedAccountNumber_AsciiHex, iIdx, 2) = strByte

That version of Mid is NOT basically Substring, because it is setting, not getting. You basically need to break up your String into three pieces, using Substring, and then create a new String from the first part and the third part and the new bit in between.

[Techno]

right. sorry, I should have been clearer. What i meant is that the function Mid$ in VB is SubString on .NET. but the actual function/logic you are saying correctly is replacing/setting the variable value.

what about a replace? would that be ok?

C#:


modAccountNumberAsciiHex = modAccountNumberAsciiHex.Replace(modAccountNumberAsciiHex.Substring((index), 2), strByte);

[ThomasJohnsen]

Depends on the contents. If the substring returns "xx" and that string is found elsewhere, you will have both replaced. You could ofc make sure that this will never happen by inserting some sort of signalstring at the location of the 2-digit hex-string.

#EDIT: In your example strings like "5f5f" could cause problems using your code.