WPF - 鼠标

有多种类型的鼠标输入，如 MouseDown、MouseEnter、MouseLeave 等。在以下示例中，我们将处理一些鼠标输入。

• 让我们创建一个新的 WPF 项目，名为 WPFMouseInput。

• 将一个矩形和三个文本块拖到堆栈面板，并设置以下属性和事件，如以下 XAML 文件所示。

<Window x:Class = "WPFMouseInput.MainWindow" 
   xmlns = "http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
   xmlns:x = "http://schemas.microsoft.com/winfx/2006/xaml" 
   xmlns:d = "http://schemas.microsoft.com/expression/blend/2008" 
   xmlns:mc = "http://schemas.openxmlformats.org/markup-compatibility/2006" 
   xmlns:local = "clr-namespace:WPFMouseInput" 
   mc:Ignorable = "d" Title = "MainWindow" Height = "350" Width = "604">
	
   <StackPanel> 
      <Rectangle x:Name = "mrRec" Fill = "AliceBlue" 
         MouseEnter = "OnMouseEnter" MouseLeave = "OnMouseLeave"  
         MouseMove = "OnMouseMove" MouseDown = "OnMouseDown" Height = "100" Margin = "20"> 
      </Rectangle> 
		
      <TextBlock x:Name = "txt1" Height = "31" HorizontalAlignment = "Right" 
         Width = "250" Margin = "0,0,294,0" /> 
      <TextBlock x:Name = "txt2" Height = "31" HorizontalAlignment = "Right"  
         Width = "250" Margin = "0,0,294,0" /> 
      <TextBlock x:Name = "txt3" Height = "31" HorizontalAlignment = "Right"  
         Width = "250" Margin = "0,0,294,0" /> 
			
   </StackPanel> 
	
</Window>

以下是处理不同鼠标事件的 C# 代码。

using System.Windows; 
using System.Windows.Input; 
using System.Windows.Media; 
using System.Windows.Shapes; 
 
namespace WPFMouseInput { 

   public partial class MainWindow : Window {
	
      public MainWindow() { 
         InitializeComponent(); 
      } 
		
      private void OnMouseEnter(object sender, MouseEventArgs e) { 
         Rectangle source = e.Source as Rectangle; 
			
         if (source != null) { 
            source.Fill = Brushes.SlateGray; 
         } 
			
         txt1.Text = "Mouse Entered"; 
      } 
		
      private void OnMouseLeave(object sender, MouseEventArgs e) { 
		
         // Cast the source of the event to a Button. 
         Rectangle source = e.Source as Rectangle;
			
         // If source is a Button. 
         if (source != null) { 
            source.Fill = Brushes.AliceBlue; 
         } 
			
         txt1.Text = "Mouse Leave"; 
         txt2.Text = ""; 
         txt3.Text = ""; 
      } 
		
      private void OnMouseMove(object sender, MouseEventArgs e) { 
         Point pnt = e.GetPosition(mrRec); 
         txt2.Text = "Mouse Move: " + pnt.ToString(); 
      } 
		
      private void OnMouseDown(object sender, MouseButtonEventArgs e) { 
         Rectangle source = e.Source as Rectangle; 
         Point pnt = e.GetPosition(mrRec); 
         txt3.Text = "Mouse Click: " + pnt.ToString(); 
			
         if (source != null) { 
            source.Fill = Brushes.Beige; 
         } 
      } 
		
   } 
} 

编译并执行上述代码时，将产生以下窗口 −

当鼠标进入矩形内时，矩形的颜色会自动改变。此外，您将看到一条消息，表明鼠标已进入，并显示其坐标。

当您在矩形内单击时，它会改变颜色，并显示鼠标单击的坐标。

当鼠标离开矩形时，它将显示鼠标已离开的消息，矩形将变为其默认颜色。