WPF 和 VB.Net 倒计时器 - 未调用 Tick 事件

Question

我想通过按下按钮来更新 wpf 形式的文本块，并使用倒计时器。 目前看来我的 DispatcherTimer 的 tick 事件没有被调用。

这是我在 vb.net 中的全部代码

Private WithEvents tm5min As New DispatcherTimer
Private Sub BtnStart5_MouseDown(sender As Object, e As MouseButtonEventArgs) Handles BtnStart5.MouseDown
        Try
            tm5min.Interval = TimeSpan.FromMinutes(5)
            tm5min.Start()
            Debug.WriteLine("clock started with: " & tm5min.Interval.TotalMinutes)
        Catch ex As Exception
            Debug.Write(ex.Message)
        End Try
End Sub

Private Sub tm5min_Tick(sender As Object, e As EventArgs) Handles tm5min.Tick
        Debug.Write("I'm ticking")
        TxtCountdown.Text = Date.Now.ToString("mm\:ss")
End Sub

Answer 1

使用当前代码使用鼠标右键触发事件。

否则

Private Sub btns_Click(sender As Object, e As RoutedEventArgs) Handles btns.Click Try tm5min.Interval = TimeSpan.FromSeconds(5) tm5min.Start() Debug.WriteLine("clock started with: " & tm5min.Interval.TotalMinutes) Catch ex As Exception Debug.Write(ex.Message) End Try End Sub