vb的GUID生成算法的方法介绍

vb的GUID生成算法的方法介绍

源代码推荐:vb的GUID生成算法

'RETURNS:GUID if successful; blank string otherwise.
'Unlike the GUIDS in the registry, this function returns GUID
'without "-" characters.See comments for how to modify if you
'want the dash.

Public Function GUID() As String
Dim lRetVal As Long
Dim udtGuid As GUID

Dim sPartOne As String
Dim sPartTwo As String
Dim sPartThree As String
Dim sPartFour As String
Dim iDataLen As Integer
Dim iStrLen As Integer
Dim iCtr As Integer
Dim sAns As String

On Error GoTo errorhandler
sAns = ""

lRetVal = CoCreateGuid(udtGuid)

If lRetVal = 0 Then

'First 8 chars
sPartOne = Hex$(udtGuid.PartOne)
iStrLen = Len(sPartOne)
iDataLen = Len(udtGuid.PartOne)
sPartOne = String((iDataLen * 2) - iStrLen, "0") _
& Trim$(sPartOne)

'Next 4 Chars
sPartTwo = Hex$(udtGuid.PartTwo)
iStrLen = Len(sPartTwo)
iDataLen = Len(udtGuid.PartTwo)
sPartTwo = String((iDataLen * 2) - iStrLen, "0") _
& Trim$(sPartTwo)

'Next 4 Chars
sPartThree = Hex$(udtGuid.PartThree)
iStrLen = Len(sPartThree)
iDataLen = Len(udtGuid.PartThree)
sPartThree = String((iDataLen * 2) - iStrLen, "0") _
& Trim$(sPartThree)'Next 2 bytes (4 hex digits)

'Final 16 chars
For iCtr = 0 To 7
sPartFour = sPartFour & _
Format$(Hex$(udtGuid.PartFour(iCtr)), "00")
Next

'To create GUID with "-", change line below to:
'sAns = sPartOne & "-" & sPartTwo & "-" & sPartThree _
'& "-" & sPartFour

sAns = sPartOne & sPartTwo & sPartThree & sPartFour

End If

GUID = sAns
Exit Function


errorhandler:
'return a blank string if there's an error
Exit Function
End Function