' DateToInteger8.vbs
' VBScript program demonstrating how to convert a datetime value to
' the corresponding Integer8 (64-bit) value. The Integer8 value is the
' number of 100-nanosecond intervals since 12:00 AM January 1, 1601,
' in Coordinated Universal Time (UTC). The conversion is only accurate
' to the nearest second, so the Integer8 value will always end in at
' least 7 zeros.
'
' ----------------------------------------------------------------------
' Copyright (c) 2004 Richard L. Mueller
' Hilltop Lab web site - http://www.rlmueller.net
' Version 1.0 - June 11, 2004
'
' You have a royalty-free right to use, modify, reproduce, and
' distribute this script file in any way you find useful, provided that
' you agree that the copyright owner above has no warranty, obligations,
' or liability for such use.

Option Explicit

Dim dtmDateValue, dtmAdjusted, lngSeconds, str64Bit
Dim objShell, lngBiasKey, lngBias, k

If (Wscript.Arguments.Count <> 1) Then
    Wscript.Echo "Required argument <DateTime> missing"
    Wscript.Echo "For example:"
    Wscript.Echo ""
    Wscript.Echo "cscript DateToInteger8.vbs ""2/5/2004 4:58:58 PM"""
    Wscript.Echo ""
    Wscript.Echo "If the date/time value has spaces, enclose in quotes"
    Wscript.Quit
End If

dtmDateValue = CDate(Wscript.Arguments(0))

' Obtain local Time Zone bias from machine registry.
' This bias changes with Daylight Savings Time.
Set objShell = CreateObject("Wscript.Shell")
lngBiasKey = objShell.RegRead("HKLM\System\CurrentControlSet\Control\" _
    & "TimeZoneInformation\ActiveTimeBias")
If (UCase(TypeName(lngBiasKey)) = "LONG") Then
    lngBias = lngBiasKey
ElseIf (UCase(TypeName(lngBiasKey)) = "VARIANT()") Then
    lngBias = 0
    For k = 0 To UBound(lngBiasKey)
        lngBias = lngBias + (lngBiasKey(k) * 256^k)
    Next
End If

' Convert datetime value to UTC.
dtmAdjusted = DateAdd("n", lngBias, dtmDateValue)

' Find number of seconds since 1/1/1601.
lngSeconds = DateDiff("s", #1/1/1601#, dtmAdjusted)

' Convert the number of seconds to a string
' and convert to 100-nanosecond intervals.
str64Bit = CStr(lngSeconds) & "0000000"
Wscript.Echo "Integer8 value: " & str64Bit