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Generate GUIDs With One API Call

Generate GUIDs With One API Call

I read a great advanced tip on how to create a GUID in “Generate Unique String IDs” [“101 Tech Tips for VB Developers,” Supplement to VBPJ, August 1999]. However, you can use only one API call instead of four. The OLE32.dll contains a function called WinCoCreateGUID that does all the math for you. I have included a second function called PadZeros to format the GUID:

 Option ExplicitPrivate Type GUIDType	D1       As Long	D2       As Integer	D3       As Integer	D4(8)    As ByteEnd TypePrivate Declare Function WinCoCreateGuid 		Lib "OLE32.DLL" 	Alias "CoCreateGuid" (g As GUIDType) As LongPublic Function CreateGUIDString() As String	Dim g As GUIDType	Dim sBuf As String	Call WinCoCreateGuid(g)	sBuf = PadZeros(Hex$(g.D1), 8, True) & _		PadZeros(Hex$(g.D2), 4, True) & _		PadZeros(Hex$(g.D3), 4, True) & _		PadZeros(Hex$(g.D4(0)), 2) & _		PadZeros(Hex$(g.D4(1)), 2, True) & _		PadZeros(Hex$(g.D4(2)), 2) & _		PadZeros(Hex$(g.D4(3)), 2) & _		PadZeros(Hex$(g.D4(4)), 2) & _		PadZeros(Hex$(g.D4(5)), 2) & _		PadZeros(Hex$(g.D4(6)), 2) & _		PadZeros(Hex$(g.D4(7)), 2)	CreateGUIDString = sBufEnd FunctionPrivate Function PadZeros(ByVal sBit As String, _	ByVal iStrLen As Integer, Optional bHyphen _	As Boolean) As String	If iStrLen > Len(sBit) Then		sBit = Right$(String$((iStrLen - Len(sBit)), _			"0") & sBit, iStrLen)	End If	If bHyphen Then sBit = sBit & "-"	PadZeros = sBitEnd Function

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