没有两个回调的C＃wpf网格点击事件

Question

现在我正在使用MouseLeftButtonUp事件检测网格中的点击次数。

但是，每当我打开一个OpenFileDialog并选择一个文件。鼠标上移事件通过对话框并在我的网格上注册一个鼠标上移事件。

如何在我的网格上检测有效的鼠标点击（鼠标向下并向上移动鼠标），而无需创建多个回调来跟踪我的元素是否实际单击并且不会在鼠标悬停时发生？

例子：

System.Windows.Forms.OpenFileDialog o; 


o = new System.Windows.Forms.OpenFileDialog(); 

if (o.ShowDialog() == System.Windows.Forms.DialogResult.OK) 
{ 

} 

当我双击对话框中的文件和我的格子窗后面。鼠标向上事件被调用。

Answer 1

有没有简单的方法来处理Click事件没有两个回调在Grid。但是我们可以编写一些帮助代码来实现它。

这是你可以使用我的助手代码：以上

<Grid Background="Transparent"> 
    <local:RoutedEventExtension.Event> 
     <local:ClickEvent Click="Grid_Click"></local:ClickEvent> 
    </local:RoutedEventExtension.Event> 
</Grid> 

XAML。

private void Grid_Click(object sender, EventArgs e) 
{ 
    // Write your event handler code here. 
} 

C＃以上。

这是我的助手代码：

public abstract class RoutedEventExtension 
{ 
    public static readonly DependencyProperty EventProperty = DependencyProperty.RegisterAttached(
     "Event", typeof(RoutedEventExtension), typeof(RoutedEventExtension), 
     new PropertyMetadata(null, OnEventChanged)); 

    public static void SetEvent(DependencyObject element, RoutedEventExtension value) 
    { 
     element.SetValue(EventProperty, value); 
    } 

    public static RoutedEventExtension GetEvent(DependencyObject element) 
    { 
     return (RoutedEventExtension) element.GetValue(EventProperty); 
    } 

    private static void OnEventChanged(DependencyObject d, DependencyPropertyChangedEventArgs e) 
    { 
     if (!(d is IInputElement element)) 
     { 
      throw new InvalidOperationException("RoutedEventExtension can only be attached on an IInputElement."); 
     } 

     var oldValue = (RoutedEventExtension) e.OldValue; 
     var newValue = (RoutedEventExtension) e.NewValue; 

     oldValue?.Detach(); 
     newValue.Attach(element); 
    } 

    protected IInputElement Target { get; private set; } 

    private void Attach(IInputElement target) 
    { 
     Target = target; 
     OnAttached(); 
    } 

    private void Detach() 
    { 
     try 
     { 
      OnDetaching(); 
     } 
     finally 
     { 
      Target = null; 
     } 
    } 

    protected abstract void OnAttached(); 

    protected abstract void OnDetaching(); 
} 

public sealed class ClickEvent : RoutedEventExtension 
{ 
    public event EventHandler Click; 

    protected override void OnAttached() 
    { 
     Target.MouseLeftButtonDown += OnMouseLeftButtonDown; 
     Target.MouseLeftButtonUp += OnMouseLeftButtonUp; 
     Target.LostMouseCapture += OnLostMouseCapture; 
    } 

    protected override void OnDetaching() 
    { 
     Target.MouseLeftButtonDown -= OnMouseLeftButtonDown; 
     Target.MouseLeftButtonUp -= OnMouseLeftButtonUp; 
     Target.LostMouseCapture -= OnLostMouseCapture; 
    } 

    private bool _isMouseDown; 

    private void OnMouseLeftButtonDown(object sender, MouseButtonEventArgs e) 
    { 
     _isMouseDown = true; 
     Mouse.Capture(Target); 
    } 

    private void OnMouseLeftButtonUp(object sender, MouseButtonEventArgs e) 
    { 
     if (!_isMouseDown) 
     { 
      return; 
     } 

     Mouse.Capture(null); 
     OnClick(); 
    } 

    private void OnLostMouseCapture(object sender, MouseEventArgs e) 
    { 
     _isMouseDown = false; 
    } 

    private void OnClick() 
    { 
     Click?.Invoke(this, EventArgs.Empty); 
    } 
} 

助手代码包含两个班。一种提供一种常见的方式来附加IInputElement上的任何事件，另一种提供基本的Click实现。

您可以通过继承自RoutedEventExtension自己编写自己的其他事件实现。