Win8应用程序中的计时器计数

Question

我正在构建一个win8应用程序，它有3个按钮（Button1，Button2和StartButton）和计时器。 Button1和Button2被禁用。如果单击StartButton，Button1被启用，并且20秒内的点击次数被计入并显示在文本块1中。定时器结束后，Button1被禁用，Button2被启用，点击被计数并显示在textblock2中。我的问题是，计时器适用于Button1而不适用于Button2。当启用按钮2时，计时器变快。有人能帮我吗？ 我的代码如下：

private int count1=0; 
    private int count2=0; 
    private int clickCounter = 0; 
    private int timeLeft; 
    private DispatcherTimer timer; 

    private void StartTimer() 
    { 
     if (this.timer != null) 
     { 
      this.StopTimer(); 
     } 
     DispatcherTimer timer = new DispatcherTimer(); 
     timer.Interval = new TimeSpan(0,0,0,1); 
     timer.Tick += timer_Tick; 
     timer.Start(); 

    } 

    private void StopTimer() 
    { 
     if (this.timer != null) 
     { 
      this.timer.Stop(); 
      this.timer = null; 
     } 
    } 

    public void timer_Tick(object sender, object args) 
    { 

     if (timeLeft > 0) 
     { 
      timeLeft = timeLeft - 1; 
      timerTextBlock.Text = Convert.ToString(timeLeft); 
      this.StartButton.IsEnabled = false; 
     } 
     else 
     { 
      StopTimer(); 
      if (clickCounter==2) 
      { 
       ShowResult(); 
       this.Button2.IsEnabled = false; 
       this.StartButton.IsEnabled = false; 
      } 
      else 
      { 
       myMsg.Text = "Time's up!"; 
       this.Button1.IsEnabled = false; 
       this.StartButton.IsEnabled = true; 
      } 
     } 
    } 

    private void Button1_Click(object sender, Windows.UI.Xaml.RoutedEventArgs e) 
    { 
     // TODO: Add event handler implementation here. 
     count1++; 
     this.textblock1.Text=count1.ToString(); 

    } 

    private void Button2_Click(object sender, Windows.UI.Xaml.RoutedEventArgs e) 
    { 
     count2++; 
     this.textblock2.Text=count2.ToString(); 
    } 
    public void ResetTimer() 
    { 
      timeLeft = 20; 
    } 
    private void StartButton_Click(object sender, RoutedEventArgs e) 
    { 
     clickCounter++; 
     if (textblock1.Text == "0") 
     { 
      ResetTimer(); 
      StartTimer(); 
      this.Button1.IsEnabled = true; 
     } 
     else 
     { 
      ResetTimer(); 
      StartTimer(); 
      this.Button2.IsEnabled = true; 
     } 
    } 

Answer 1

每次调用执行StartTimer方法timer.Tick += timer_Tick;。这意味着如果您第二次致电StartTimer，则每个勾号将调用两个事件。拆分您的代码，如：

private void InitTimer() 
{ 
    timer = new DispatcherTimer(); 
    timer.Interval = new TimeSpan(0,0,0,1); 
    timer.Tick += timer_Tick; 
} 

private void StartTimer() 
{ 
    timer.Start(); 
} 

并且只调用InitTimer。另一种选择是取消注册if (this.timer != null)中的事件 我看到的第二点是命名冲突：您的StartTimer方法中有一个私有全局变量计时器和一个变量计时器。

//编辑：全更新的代码：

private int count1=0; 
private int count2=0; 
private int clickCounter = 0; 
private int timeLeft; 
private DispatcherTimer timer; 

private void StartTimer() { 
    if (timer == null) { 
     timer = new DispatcherTimer(); 
     timer.Interval = new TimeSpan(0,0,0,1); 
     timer.Tick += timer_Tick; 
    } 
    timer.Stop(); 
    timeLeft = 20; 
    timer.Start(); 
} 

public void timer_Tick(object sender, object args) { 
    if (timeLeft > 0) { 
     timeLeft = timeLeft - 1; 
     timerTextBlock.Text = Convert.ToString(timeLeft); 
    } else { 
     timer.Stop(); 
     if (clickCounter==2) { 
      ShowResult(); 
      Button2.IsEnabled = false; 
      StartButton.IsEnabled = false; 
     } else { 
      myMsg.Text = "Time's up!"; 
      Button1.IsEnabled = false; 
      StartButton.IsEnabled = true; 
     } 
    } 
} 

private void Button1_Click(object sender, Windows.UI.Xaml.RoutedEventArgs e) { 
    count1++; 
    textblock1.Text=count1.ToString(); 
} 

private void Button2_Click(object sender, Windows.UI.Xaml.RoutedEventArgs e) { 
    count2++; 
    textblock2.Text=count2.ToString(); 
} 

private void StartButton_Click(object sender, RoutedEventArgs e) { 
    clickCounter++; 
    StartButton.IsEnabled = false; 
    if (textblock1.Text == "0"){ 
     Button1.IsEnabled = true; 
     StartTimer(); 
    } else { 
     Button2.IsEnabled = true; 
     StartTimer(); 
    } 
}