How to: Convert Local Time to UTC

Article
08/02/2010
Windows Management Instrumentation (WMI) functions that use time information, such as the ClearPasswordHistory Method function or the ClearRuns Method function, require that you use Coordinated Universal Time (UTC, also known as Greenwich Mean Time).
The following Microsoft Visual Basic Scripting Edition (VBScript) example converts local time to UTC.
Option Explicit

On Error Resume Next

Set objArgs = WScript.Arguments
Dim convertYear,convertMonth,convertDay,convertHour,convertMin,convertSec,convertMil,AMPM,ToUTC,TimeConst

' Fill In Default settings.
ToUTC = True
TimeConst = "UTC"
AMPM = "am"
convertMil = "000"

LoadArgs 
ValidateInput
convertHour = FormatHour(convertHour)

Wscript.Echo ConvertToUTC(convertYear & convertMonth & convertDay & convertHour & convertMin & convertSec) & " " & TimeConst

Function ConvertToUTC(strTime)
    On Error Resume Next

    ' Parses a date time string passing in the following format:
    ' 20040806065423 - Year Month Day Hour Minutes Seconds.

    Dim strDateTime, UTCDate, Computer
    Dim YerArg : YerArg = left(strTime,4   )
    Dim MonArg : MonArg = mid (strTime,5,2 )
    Dim DayArg : DayArg = mid (strTime,7,2 )
    Dim HrsArg : HrsArg = mid (strTime,9,2 ) 
    Dim MinArg : MinArg = mid (strTime,11,2)
    Dim SecArg : SecArg = mid (strTime,13,2)

    ' Use Win32_ComputerSystem CurrentTimeZone property, because it automatically adjusts the
    ' Time Zone bias for daylight saving time; Win32_Time Zone Bias property does not.

   ' Get the computer’s current time zone offset.
    For Each LocalTimeZone in GetObject("winmgmts:").InstancesOf("Win32_ComputerSystem")
    TimeZoneOffset = LocalTimeZone.CurrentTimeZone
    Next

    ' Wscript.Echo "The current time difference is " & TimeZoneOffset & " minutes (" & TimeZoneOffset/60 & " hrs)" 

    strDateTime = MonArg & "-" & DayArg & "-" & YerArg & " " & HrsArg & ":" & MinArg & ":" & SecArg

    if TimeZoneOffset < 0 Then
    if ToUTC then
        UTCDate = DateAdd("n",  ABS(TimeZoneOffset), strDateTime)
    else
        UTCDate = DateAdd("n", -ABS(TimeZoneOffset), strDateTime)
    end if
    else
    if ToUTC then
        UTCDate = DateAdd("n", -ABS(TimeZoneOffset), strDateTime)
    else
        UTCDate = DateAdd("n", ABS(TimeZoneOffset), strDateTime)
    end if
    end if

    If Err.Number <> 0 Then 
    Wscript.Echo "ConvertToUTC::Invalid Argument"
    Usage
    End If

    ConvertToUTC = Trim(Year(UTCDate) & "-" & FormatArgs(Month(UTCDate)) & "-" & FormatArgs(Day(UTCDate)) & " " & FormatArgs(Hour(UTCDate)) & ":" & FormatArgs(Minute(UTCDate)) & ":" & FormatArgs(Second(UTCDate))) & "." & convertMil

End Function

Sub Usage
    Wscript.Echo vbCrLf & "cscript ConvertUTC.vbs [Year Month Day] [Hour Min Sec [MilSec]] [AM/PM] [U/L]"
    Wscript.Echo vbCrLf & "Year      Year"
    Wscript.Echo "Month     Month"
    Wscript.Echo "Day       Day"
    Wscript.Echo "Hour      Hour"
    Wscript.Echo "Min       Minutes"
    Wscript.Echo "Sec       Seconds"
    Wscript.Echo "MilSec    Milliseconds [000 default]"
    Wscript.Echo "AM/PM     For non 24 hour time specify AM or PM [AM default]"
    Wscript.Echo "U/L       Specify the direction for the conversion:"
    Wscript.Echo "           U = Local time to UTC time [default]"
    Wscript.Echo "           L = UTC time to local time" & vbcrlf
    Wscript.Echo vbCrLf & "Usage Examples:"
    Wscript.Echo "1) cscript ConvertUTC.vbs U or cscript ConvertUTC.vbs"
    Wscript.Echo "2) cscript ConvertUTC.vbs L"
    Wscript.Echo "3) cscript ConvertUTC.vbs 2004 12 31 5 55 55 p"
    Wscript.Echo "3) cscript ConvertUTC.vbs 2004 12 31 17 55 55 123 u"
    Wscript.Echo "4) cscript ConvertUTC.vbs 17 55 55 l"
    Wscript.Echo "5) cscript ConvertUTC.vbs 17 55 55 u"
    Wscript.Echo "6) cscript ConvertUTC.vbs 5 55 55 123 p u"
    Wscript.Echo vbCrLf & "Results:" & vbcrlf & "1) Converts Local now to UTC now  [2004-08-11 23:22:19.000 UTC  ]"
    Wscript.Echo "2) Converts UTC now to Local now  [2004-08-11 09:22:19.000 Local]"
    Wscript.Echo "3) 2005-01-01 00:55:55.000 UTC"
    Wscript.Echo "4) 2004-08-11 10:55:55.000 Local"
    Wscript.Echo "5) 2004-08-12 00:55:55.000 UTC"
    Wscript.Echo "6) 2004-08-12 00:55:55.123 UTC"
    Wscript.Quit(1)
End Sub

Sub LoadArgs
    On Error Resume Next 
    if objArgs.Count > 0 Then
        If IsNumeric(objArgs(0)) Then
        if Len(objArgs(0)) = 4 Then
            convertYear  = CheckYear (objArgs(0))
        convertMonth = FormatArgs(objArgs(1))
        convertDay   = FormatArgs(objArgs(2))
        convertHour  = FormatArgs(objArgs(3))
        convertMin   = FormatArgs(objArgs(4))
        convertSec   = FormatArgs(objArgs(5))

        If objArgs.Count >= 7 then 
            if IsNumeric(objArgs(6)) Then
                convertMil = FormatMil (objArgs(6))
            Else
                SetValues(objArgs(6))
            end if
        End if
    
            If objArgs.Count >= 8 then SetValues(objArgs(7))
            If objArgs.Count = 9 then SetValues(objArgs(8))

        If Err.Number <> 0 Then 
            WScript.Echo "LoadArgs::Invalid arguments"
            Usage
        End If   

        Else

        ' Did not pass in Year Month Day arguments just time.
        LoadDefaults
        convertHour  = FormatArgs(objArgs(0))
        convertMin   = FormatArgs(objArgs(1))
        convertSec   = FormatArgs(objArgs(2))
        If objArgs.Count >= 4 then 
            If IsNumeric(objArgs(3)) Then
            convertMil = FormatMil (objArgs(3))
            Else
                SetValues(objArgs(3))
            End If
              End if
              If objArgs.Count >= 5 then SetValues(objArgs(4))
              If objArgs.Count = 6 then SetValues(objArgs(5))
       End If
    Else

        ' First Argument IS NOT numerical value.
       LoadDefaults
            SetValues(objArgs(0))
    End If
    Else

    ' Nothing passed as args.
    LoadDefaults
    End If
End Sub

Function FormatHour(ArgVal)
    Select Case AMPM
        Case "pm"
        If convertHour < 12 Then ArgVal = convertHour + 12
        Case "am"
        If convertHour = 12 Then ArgVal = "00"
    End Select

    FormatHour = ArgVal
End Function

Sub SetValues(Arg)
    Dim SetVal : SetVal = Flase
   
    Select Case Left(lcase(arg),1)
    Case "u"
        TimeConst = "UTC"
        ToUTC = True
        SetVal = True
    Case "l"
        TimeConst = "Local"
        ToUTC = False
        SetVal = True
    Case "a"
        AMPM = "am"
        SetVal = True
    Case "p"
        AMPM = "pm"
        SetVal = True
    End Select

    If IsNumeric(Left(arg,1)) or Not SetVal Then
    WScript.Echo "SetValues::Invalid arguments"
    Usage
    End If

End Sub

Sub LoadDefaults
    CurTime = Now
    convertYear  = Year(CurTime)
    convertMonth = FormatArgs(Month(CurTime))
    convertDay   = FormatArgs(Day(CurTime))
    convertHour  = FormatArgs(Hour(CurTime))
    convertMin   = FormatArgs(Minute(CurTime))
    convertSec   = FormatArgs(Second(CurTime))
    ToUTC = True

End Sub

Sub ValidateInput
    Dim ValErr
    ValErr = 0
    If convertHour  > 23 Then ValErr = 1
    If convertDay   > 31 Then ValErr = 1
    If convertMonth > 12 Then ValErr = 1
    If convertMin   > 59 Then ValErr = 1
    If convertSec   > 59 Then ValErr = 1
    If ValErr > 0 Then
    WScript.Echo "ValidateInput::Invalid arguments"
    Usage
    End if
End Sub

Function FormatArgs(str)
    if Len(str) < 2 Then str = "0" & str
    FormatArgs = str
    If not IsNumeric(str) Then 
    WScript.Echo "FormatArgs::Invalid arguments"
    Usage
    End If
End Function

Function CheckYear(str)

    CheckYear = str

    If not IsNumeric(str) or Len(str) <> 4 Then 
    WScript.Echo "CheckYear::Invalid arguments"
    Usage
    End If

End Function

Function FormatMil(str)
    tStr = str
    if Len(str) < 3 Then 
    for i = Len(str) + 1 to 3
        tStr = tStr+ "0"
    Next
    end if

    if Len(tStr) > 3 then tStr = Left(tStr,3)
    FormatMil = tStr
    If not IsNumeric(tStr) Then 
    WScript.Echo "FormatMil::Invalid arguments"
    Usage
    End If
End Function

Sub ErrorHandler (ErrorMessage)
    WScript.Echo ErrorMessage
    WScript.Quit(1)
End Sub
How to: Convert Local Time to UTC

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