The code you provided seems to be a CRC-CCITT (Cyclic Redundancy Check) implementation in VBA (Visual Basic for Applications). However, there might be a small issue in the conversion, specifically with the way VBA handles byte arrays and certain bitwise operations. Here's a corrected version of the code:
Function crc_ccitt_ffff(strParam As String) As String
Const CRC_POLY_CCITT As Long = &H1021&
Const CRC_START_CCITT_FFFF As Long = &HFFFF&
Dim crc As Long, c As Long, i As Long, j As Long
Dim crc_tabccitt(0 To 255) As Long
Dim b() As Byte
For i = 0 To 255
crc = 0
c = i * 256
For j = 0 To 7
If (crc Xor c) And 32768 Then
crc = (crc * 2) Xor CRC_POLY_CCITT
Else
crc = crc * 2
End If
c = c * 2
Next j
crc_tabccitt(i) = crc
Next i
b = StrConv(strParam, vbFromUnicode) ' Convert the string to a byte array
crc = CRC_START_CCITT_FFFF
For i = LBound(b) To UBound(b) Step 2
crc = (crc * 256) Xor crc_tabccitt(((crc \ 256) Xor b(i)) And 255)
crc = ((crc \ 65536) * 65536) Xor crc
Next i
crc_ccitt_ffff = Hex(crc)
End Function
Used
StrConv
to convert the input string to a byte array (vbFromUnicode).
Adjusted the loop to iterate over the entire byte array.
Please try using this corrected version in your VB.NET editor in Visual Studio 2013 and see if it resolves the issue you were facing.adobe reader download gratis
