vb.net减去日期和时间

你好，我有这么多的问题，试图得到正确的，这让我疯狂我想做的是，我有一个开始和停止按钮的形式开始和停止时间。我用excel作为我的数据库好的。我需要做的是，当你按下start时，它会将现在的时间记录到excel单元格中。我们会说A1我记录它，因为我可能会关闭程序，然后当你回到程序中，我点击停止，我需要获取开始时间，然后从现在的时间中减去它，比如

span=Datetime.Now.starttime

然后，我需要用h:mm格式的时间，因为它只需要几个小时和几分钟，然后用excel中的A2。在上面的h:mm格式中，这里还有一个问题！说我回去重新开始工作！再次让它把现在的时间放在A1，然后我去停止我的时间

如果oXL.RangeA2.Value=则

然后我需要它做它以前做过的事情，取停止时间，从开始时间中减去它，然后把它放在格式h:mm中，然后把它加到A2中的时间，这将是所有的总时间！请帮帮我，我已经做了好几个小时了。这是我真正的代码，但我已经对它做了很多修改，如果你能给我一个A1和A2的示例程序，我就可以让它为我想做的工作而工作。因为我的程序非常庞大，需要很长时间才能解释清楚。多谢各位

  Private Sub btnStop_Click(sender As Object, e As EventArgs) Handles btnStop.Click
        Dim Found As Excel.Range
        Dim EndDate As String = DateTime.Now.ToString("MM-dd-yyyy")
        Dim EndTime As String = DateTime.Now
        Dim TotalTime As String
        Dim CompleteTime As TimeSpan
        Dim result As String

        strJob = InputBox("Enter Job Number")
        strInitials = InputBox("Enter Initials.")


        If strJob = "" Then
            MsgBox("You have to enter a Job Number.")
            Exit Sub
        End If

        If strInitials = "" Then
            MsgBox("You have to enter your Initials.")
            Exit Sub
        End If

        Found = oSheet.Cells.Find(strJob)

        If Found Is Nothing Then
            MsgBox("Job was not found.")

        Else
            Found.Activate()

            'Check for Programmer one.
            If oXL.ActiveCell.Offset(0, 2).Value = "" Then
                MsgBox("This job has not been started")
                Exit Sub

            ElseIf oXL.ActiveCell.Offset(0, 2).Value = strInitials Then
                If oXL.ActiveCell.Offset(0, 13).Value = Nothing Then
                    MsgBox("You have not started this job yet")
                    Exit Sub
                End If

                Dim time1 As DateTime = oXL.ActiveCell.Offset(0, 13).Value
                If oXL.ActiveCell.Offset(0, 7).Value = Nothing Then
                    Dim span As TimeSpan
                    span = DateTime.Now.Subtract(time1)
                    TotalTime = (span.Days * 24) + span.Hours & ":" & (span.Minutes)
                    oXL.ActiveCell.Offset(0, 7).Value = TotalTime
                Else

                    Dim time3 = TimeSpan.ParseExact(oXL.ActiveCell.Offset(0, 7).Value, "h\:mm", CultureInfo.CurrentCulture)
                    Dim span As TimeSpan
                    span = DateTime.Now.Subtract(time1)
                    TotalTime = span.Hours & ":" & (span.Minutes)
                    oXL.ActiveCell.Offset(0, 14).Value = TotalTime
                    Dim time2 = TimeSpan.ParseExact(oXL.ActiveCell.Offset(0, 114).Value, "h\:mm", CultureInfo.CurrentCulture)
                    CompleteTime = time2 + time3
                    oXL.ActiveCell.Offset(0, 7).Value = CompleteTime
                End If
                oXL.ActiveCell.Offset(0, 13).Value = ""
                oXL.ActiveCell.Offset(0, 14).Value = ""


                result = MessageBox.Show("Is this job complete?", "Complete", MessageBoxButtons.YesNo)
                If result = DialogResult.No Then

                ElseIf result = DialogResult.Yes Then
                    oXL.ActiveCell.Offset(0, 4).Value = EndDate
                End If

                'Check for programmer two.
            ElseIf oXL.ActiveCell.Offset(0, 10).Value = "" Then
                MsgBox("You Are not working on this job")
                Exit Sub
            ElseIf oXL.ActiveCell.Offset(0, 10).Value = strInitials Then

                If oXL.ActiveCell.Offset(0, 17).Value = Nothing Then
                    MsgBox("You have not started this job yet")
                    Exit Sub
                End If

                Dim time1 As DateTime = oXL.ActiveCell.Offset(0, 17).Value
                'Dim time1 = TimeSpan.ParseExact(oXL.ActiveCell.Offset(0, 17).Value, "h\:mm", CultureInfo.CurrentCulture)
                'Dim time2 = TimeSpan.ParseExact(oXL.ActiveCell.Offset(0, 18).Value, "h\:mm", CultureInfo.CurrentCulture)
                If oXL.ActiveCell.Offset(0, 12).Value = Nothing Then
                    Dim span As TimeSpan
                    span = DateTime.Now.Subtract(time1)
                    TotalTime = (span.Days * 24) + span.Hours & ":" & (span.Minutes)
                    oXL.ActiveCell.Offset(0, 12).Value = TotalTime

                Else
                    Dim time2 = TimeSpan.ParseExact(oXL.ActiveCell.Offset(0, 12).Value, "h\:mm", CultureInfo.CurrentCulture)

                    Dim span As TimeSpan
                    span = DateTime.Now.Subtract(time1)
                    TotalTime = span.Hours & ":" & (span.Minutes)
                    oXL.ActiveCell.Offset(0, 18).Value = TotalTime
                    Dim time3 = TimeSpan.ParseExact(oXL.ActiveCell.Offset(0, 18).Value, "h\:mm", CultureInfo.CurrentCulture)
                    CompleteTime = time2 + time3
                    oXL.ActiveCell.Offset(0, 12).Value = CompleteTime
                End If
                oXL.ActiveCell.Offset(0, 17).Value = ""
                oXL.ActiveCell.Offset(0, 18).Value = ""
                oXL.ActiveCell.Offset(0, 12).Value = CompleteTime.ToString("h\:mm")


                result = MessageBox.Show("Is this job complete?", "Complete", MessageBoxButtons.YesNo)
                If result = DialogResult.No Then

                ElseIf result = DialogResult.Yes Then
                    oXL.ActiveCell.Offset(0, 4).Value = EndDate
                End If

            Else
                MsgBox("You Are not working on this job")
                Exit Sub

            End If

        End If

        'Logging
        If dicLogs & ".txt" = "" Then
            Dim LogBook = File.Create(dicLogs & ".txt")
            Dim logwriter As New System.IO.StreamWriter(LogBook)
            logwriter.Write(user & " Stopped " & strJob)
            logwriter.Close()
        Else
            Dim logwriter As New System.IO.StreamWriter(dicLogs & ".txt", True)
            logwriter.Write(vbNewLine & user & " Stopped " & strJob)
            logwriter.Close()

        End If

        save()
    End Sub

---

您是说只需要在应用程序外部存储两个值吗？如果是这样，那么您就不需要数据库或Excel，因为它实际上不是数据库。您只需添加DateTime和TimeSpan类型的两个应用程序设置。您只需在代码中使用My.Settings的两个属性，应用程序就会自动保存和加载它们。将Option Strict置于代码文件的顶部，或在项目的属性中设置它。当您从另一个日期时间减去一个日期时间时，您将得到一个TimeSpan对象。您可以使用TimeSpan的.ToString方法来显示差异，以您想要的格式显示。要以所需格式显示时间跨度，可以尝试：oXL.ActiveCell.Offset0，18.Value=span。ToString@hh\:mm@ChrisDunaway-VB.NET不需要@