Visual Basic 中的计时器答案

【问题标题】：Timer in Visual BasicVisual Basic 中的计时器
【发布时间】：2019-10-01 00:57:41
【问题描述】：

目前我正在尝试在 Visual Basic 中创建一个需要启动、恢复/暂停和停止方法的计时器。但是当我添加停止方法时，计时器确实停止但没有重置计时器的值。有时当我尝试再次启动它时，计时器会滴答作响（例如：-15：-44：-12）。你能帮我么？任何帮助和建议都会有很大帮助。

这是我最近一直在工作的代码

Public Class Form1
    Dim StartTime As DateTime 'old current time
    Dim PauseTime As DateTime 'keep track of the time when the timer is paused
    Dim TotalTimePaused As TimeSpan 'The total amount of time paused

    Private Sub BtnStart1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtnStart1.Click
        BtnStart1.Enabled = False
        BtnPause1.Enabled = True
        StartTime = DateTime.Now()
        Timer1.Start()
    End Sub
    Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
        'Subtract the current "Now" time from the start time
        'and then subtract the total time paused
        Dim ElapsedTime As TimeSpan = DateAndTime.Now.Subtract(StartTime).Subtract(TotalTimePaused)
        Label2.Text = ElapsedTime.Hours.ToString.PadLeft(2, "0"c) + ":" + ElapsedTime.Minutes.ToString.PadLeft(2, "0"c) + ":" + ElapsedTime.Seconds.ToString.PadLeft(2, "0"c)
        'And if you wanted the total elapsed time from time of start then
        'subtract the current "Now" time from the start time only.
    End Sub
    Private Sub BtnPause1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtnPause1.Click
        If Timer1.Enabled = False Then
            BtnPause1.Text = "Pause"
            'Add to the total time paused; the current time minus the 
            'time of pause.  this will be the total amount of time
            'paused so you can subtract it from the total amount of
            'time since the start button was pressed
            TotalTimePaused = TotalTimePaused.Add(DateAndTime.Now.Subtract(PauseTime))
            Timer1.Enabled = True
        Else
            BtnPause1.Text = "Resume"
            Timer1.Enabled = False
            'Set the pause time so it can be
            'calculated to the total time paused.
            'when the timer is resumed
            PauseTime = DateAndTime.Now
        End If
    End Sub

    Private Sub BtnStop1_Click(sender As Object, e As EventArgs) Handles BtnStop1.Click
        If Timer1.Enabled = False Then
            BtnStart1.Enabled = True
            BtnPause1.Text = "Pause"
            TotalTimePaused = TotalTimePaused.Add(DateAndTime.Now.Subtract(PauseTime))
        Else
            Timer1.Enabled = True
        End If
    End Sub
End Class

【问题讨论】：

你不允许使用Stopwatch类吗？

标签： vb.net timer

【解决方案1】：

你有这个功能

Private Sub BtnStop1_Click(sender As Object, e As EventArgs) Handles BtnStop1.Click
    If Timer1.Enabled = False Then
        BtnStart1.Enabled = True
        BtnPause1.Text = "Pause"
        TotalTimePaused = TotalTimePaused.Add(DateAndTime.Now.Subtract(PauseTime))
    Else
        Timer1.Enabled = True
    End If
End Sub

你停止计时器的地方，我认为你应该改变这个......

Private Sub BtnStop1_Click(sender As Object, e As EventArgs) Handles BtnStop1.Click
    If Timer1.Enabled = True Then
       Timer1.Enabled= False 'Here you stop the timer and 
                             'when you clic the start button this starts on
                             'on your time.
        BtnStart1.Enabled = True
        BtnPause1.Text = "Pause"
        TotalTimePaused = TotalTimePaused.Add(DateAndTime.Now.Subtract(PauseTime))
    Else
        Timer1.Enabled = False

    End If
End Sub

你必须在计时器运行时停止它。

【讨论】：