Question

I want to code this part of a VB6 application in c#.
How can I change a long into a Hex value?

Public Function longToHex(l As Long) As String
    longToHex = Hex(l)
    If Len(longToHex) < 4 Then longToHex = String(4 - Len(longToHex), "0") & longToHex
    longToHex = Right(longToHex, 2) & Left(longToHex, 2)
End Function

Answer 1

Just format to a padded hex string:

string.Format("{0:X4}", myLong.ToString().Length / 2)

Then transpose the first two characters with the last two.

The VB6 code appears to take the length of sData divided by 2, then converts the length to a Hex string and pads it with 0s to 4 characters if needed. It then transposes the first two characters with the last two.