Function uf_TimeDiff(dtmStart As Date, dtmEnd As Date) As String
    Dim t As Long
    Dim strTime(3)
    t = DateDiff("s", dtmStart, dtmEnd)
    strTime(0) = CStr(t Mod 60) & "秒"
    strTime(1) = CStr(t \ 60 Mod 60) & "分"
    strTime(2) = CStr(t \ 60 \ 60 Mod 24) & "小时"
    strTime(3) = CStr(t \ 60 \ 60 \ 24) & "天"
   
    Dim i As Integer
    For i = 0 To 3
        If Left(strTime(i), 1) = "0" Then
            strTime(i) = ""
        End If
    Next
   
    uf_TimeDiff = strTime(3) & strTime(2) & strTime(1) & strTime(0)
End Function