稳扎稳打Silverlight(13) - 2.0交互之鼠标事件和键盘事件

<UserControl x:Class="Silverlight20.Interactive.Mouse"
        xmlns="http://scheR_170_11845@as.microsoft.com/winfx/2006/xaml/presentation"    
        xmlns:x="http://scheR_170_11845@as.microsoft.com/winfx/2006/xaml">
        
        <!--路由事件是一种可以针对元素树中的多个侦听器（而不是仅针对引发该事件的对象）调用处理程序的事件-->
        
        <!--
        MouSELEftButtonDown,MouSELEftButtonUp和MouseMove均为向上冒泡的路由事件
        本例的事件路由为：Ellipse -> StackPanel -> UserControl 或 Rectangle -> Canvas -> StackPanel -> UserControl
        如果不想向上冒泡，则可以使用 MouseButtonEventArgs.Handled = true 告知事件已被处理
        -->
        <StackPanel HorizontalAlignment="Left" MouSELEftButtonDown="StackPanel_MouSELEftButtonDown" >

                <!--
                MouseEnter - 鼠标进入时触发的事件（显然，此事件不能冒泡）
                MouSELEave - 鼠标离开时触发的事件（显然，此事件不能冒泡）
                
                MouSELEftButtonDown - 鼠标左键单击按下时触发的事件
                MouSELEftButtonUp - 鼠标左键单击按下并放开时触发的事件
                MouseMove - 鼠标移动时触发的事件
                -->
                <Ellipse x:Name="ellipse" Width="200" Height="100" Fill="Red" Margin="5"    
                        MouseEnter="ellipse_MouseEnter"    
                        MouSELEave="ellipse_MouSELEave"
                        MouSELEftButtonDown="ellipse_MouSELEftButtonDown"
                        MouSELEftButtonUp="ellipse_MouSELEftButtonUp"
                >
                </Ellipse>

                <Canvas Margin="5">

                        <!--用于演示拖放的矩形-->
                        <Rectangle x:Name="rectangle" Fill="Blue" Width="50" Height="50"
                                MouSELEftButtonDown="rectangle_MouSELEftButtonDown"
                                MouSELEftButtonUp="rectangle_MouSELEftButtonUp"
                                MouseMove="rectangle_MouseMove"
                        />
                        
                </Canvas>

        </StackPanel>
</UserControl>

using System;

using System.Collections.Generic;

using System.Linq;

using System.Net;

using System.Windows;

using System.Windows.Controls;

using System.Windows.Documents;

using System.Windows.Input;

using System.Windows.Media;

using System.Windows.Media.Animation;

using System.Windows.Shapes;

namespace Silverlight20.Interactive

{

         public partial class Mouse : UserControl

        {

                 public Mouse()

                {

                        initializeComponent();

                }

                 void ellipse_MouseEnter( object sender,MouseEventArgs E)

                {

                        ellipse.Fill = new SolidColorBrush(Colors.Yellow);

                }

                 void ellipse_MouSELEave( object sender,MouseEventArgs E)

                {

                        ellipse.Fill = new SolidColorBrush(Colors.Red);

                }

                 private void ellipse_MouSELEftButtonUp( object sender,MouseButtonEventArgs E)

                {

                        ellipse.Fill = new SolidColorBrush(Colors.Yellow);

                }

                 private void ellipse_MouSELEftButtonDown( object sender,MouseButtonEventArgs E)

                {

                        ellipse.Fill = new SolidColorBrush(Colors.bluE);

                         // MouseButtonEventArgs.Handled - 此事件是否已被处理

                         //         false - 未被处理，事件的路由为向上冒泡

                         //         true - 已被处理，事件的路由为不再冒泡

                        e.Handled = true;

                }

                 private void StackPanel_MouSELEftButtonDown( object sender,MouseButtonEventArgs E)

                {

                         // 如果鼠标单击 rectangle 对象，则 会 执行到此句

                         // 如果鼠标单击 ellipse 对象，则 不会 执行到此句，因为之前 ellipse 对象的 MouSELEftButtonDown 事件中已经设置 e.Handled = true ，所以事件不会冒泡至此

                        ellipse.Fill = new SolidColorBrush(Colors.black);

                }

                

                 // 是否正在捕获鼠标

                 private bool _isMouseCaptured;

                 // 鼠标垂直方向上的坐标

                 private double _mouseY;

                 // 鼠标水平方向上的坐标

                 private double _mouseX;

                 private void rectangle_MouSELEftButtonDown( object sender,MouseButtonEventArgs E)

                {

                         // MouseButtonEventArgs.GetPosition() - 鼠标相对于指定元素的坐标

                        _mouseY = e.GetPosition( null).Y;

                        _mouseX = e.GetPosition( null).X;

                         // CaptureMouse() - 在指定的元素上捕获鼠标

                        rectangle.CaptureMouse();

                        _isMouseCaptured = true;

                }

                 public void rectangle_MouseMove( object sender,MouseEventArgs E)

                {

                         if (_isMouseCaptured)

                        {

                                 // 移动前和移动后的鼠标 垂直方向 和 水平方向 的位置的差值

                                 double v = e.GetPosition( null).Y - _mouseY;

                                 double h = e.GetPosition( null).X - _mouseX;

                                 // 移动后的 rectangle 对象相对于 Canvas 的坐标

                                 double newTop = v + ( double)rectangle.GetValue(Canvas.TopProperty);

                                 double newLeft = h + ( double)rectangle.GetValue(Canvas.LeftProperty);

                                 // 设置 rectangle 对象的位置为新的坐标.

                                rectangle.SETVALue(Canvas.TopProperty,newTop);

                                rectangle.SETVALue(Canvas.LeftProperty,newLeft);

                                 // 更新鼠标的当前坐标

                                _mouseY = e.GetPosition( null).Y;

                                _mouseX = e.GetPosition( null).X;

                        }

                }

                 private void rectangle_MouSELEftButtonUp( object sender,MouseButtonEventArgs E)

                {

                         // ReleaseMouseCapture() - 如果指定的元素具有鼠标捕获，则释放该捕获

                        rectangle.ReleaseMouseCapture();

                        _isMouseCaptured = false;

                }

        }

}

<!--
KeyDown - 鼠标按下时触发的事件
KeyUp - 鼠标按下并放开时触发的事件
-->
<!--
KeyDown和KeyUp均为向上冒泡的路由事件，本例的事件路由为：TextBox -> Canvas -> UserControl
-->
<UserControl x:Class="Silverlight20.Interactive.Keyboard"
        xmlns="http://scheR_170_11845@as.microsoft.com/winfx/2006/xaml/presentation"    
        xmlns:x="http://scheR_170_11845@as.microsoft.com/winfx/2006/xaml"    
        x:Name="userControl"
        KeyDown="userControl_KeyDown">
        
        <Canvas>
                        
                <TextBox x:Name="textBox" Text="TextBox" />
                
        </Canvas>
        
</UserControl>

using System;

using System.Collections.Generic;

using System.Linq;

using System.Net;

using System.Windows;

using System.Windows.Controls;

using System.Windows.Documents;

using System.Windows.Input;

using System.Windows.Media;

using System.Windows.Media.Animation;

using System.Windows.Shapes;

namespace Silverlight20.Interactive

{

         public partial class Keyboard : UserControl

        {

                 public Keyboard()

                {

                        initializeComponent();

                         this.Loaded += new RoutedEventHandler(Keyboard_Loaded);

                         // 为 UserControl 注册 KeyUp 事件

                        userControl.KeyUp += new KeyEventHandler(userControl_KeyUp);

                }

                 void Keyboard_Loaded( object sender,RoutedEventArgs E)

                {

                         // 让 UserControl 获得焦点，这样该 UserControl 内的元素才能监听到键盘事件

                        userControl.Focus();

                }

                 private void userControl_KeyDown( object sender,KeyEventArgs E)

                {

                         // 获取 textBox 对象的相对于 Canvas 的 x坐标 和 y坐标

                         double x = ( double)textBox.GetValue(Canvas.LeftProperty);

                         double y = ( double)textBox.GetValue(Canvas.TopProperty);

                         // KeyEventArgs.Key - 与事件相关的键盘的按键 [System.Windows.Input.Key枚举]

                         switch (e.Key)

                        {

                                 // 按 Up 键后 textBox 对象向 上 移动 1 个像素

                                 // Up 键所对应的 e.PlatformKeyCode == 38    

                                 // 当获得的 e.Key == Key.UnkNown 时，可以使用 e.PlatformKeyCode 来确定用户所按的键

                                 case Key.Up:

                                        textBox.SETVALue(Canvas.TopProperty,y - 1);

                                         break;

                                 // 按 Down 键后 textBox 对象向 下 移动 1 个像素

                                 // Down 键所对应的 e.PlatformKeyCode == 40

                                 case Key.Down:

                                        textBox.SETVALue(Canvas.TopProperty,y + 1);

                                         break;

                                 // 按 Left 键后 textBox 对象向 左 移动 1 个像素

                                 // Left 键所对应的 e.PlatformKeyCode == 37

                                 case Key.Left:

                                        textBox.SETVALue(Canvas.LeftProperty,x - 1);

                                         break;

                                 // 按 Right 键后 textBox 对象向 右 移动 1 个像素

                                 // Right 键所对应的 e.PlatformKeyCode == 39    

                                 case Key.Right:

                                        textBox.SETVALue(Canvas.LeftProperty,x + 1);

                                         break;

                                 default:

                                         break;

                        }

                         // 同上：Key.W - 向上移动； Key.S - 向下移动； Key.A - 向左移动； Key.D - 向右移动

                         switch (e.Key)

                        {

                                 // KeyEventArgs.Handled - 是否处理过此事件

                                 // 如果在文本框内敲 W ，那么文本框会向上移动，而且文本框内也会被输入 W

                                 // 如果只想移动文本框，而不输入 W ，那么可以设置 KeyEventArgs.Handled = true 告知此事件已经被处理完毕

                                 case Key.W:

                                        textBox.SETVALue(Canvas.TopProperty,y - 1);

                                        e.Handled = true;

                                         break;

                                 case Key.S:

                                        textBox.SETVALue(Canvas.TopProperty,y + 1);

                                        e.Handled = true;

                                         break;

                                 case Key.A:

                                        textBox.SETVALue(Canvas.LeftProperty,x - 1);

                                        e.Handled = true;

                                         break;

                                 case Key.D:

                                        textBox.SETVALue(Canvas.LeftProperty,x + 1);

                                        e.Handled = true;

                                         break;

                                 default:

                                         break;

                        }

                }

                 private void userControl_KeyUp( object sender,KeyEventArgs E)

                {

                         /*

                        System.Windows.Input.Keyboard.Modifiers - 当前按下的辅助键 [System.Windows.Input.ModifierKeys枚举]

                                ModifierKeys.None - 无

                                ModifierKeys.Alt - Alt 键

                                ModifierKeys.Control - Ctrl 键

                                ModifierKeys.Shift - Shift 键

                                ModifierKeys.Windows - Windows 键

                                ModifierKeys.Apple - Apple 键（苹果电脑）

                        */

                         // 按 Ctrl + M 则将 textBox 的位置设置为其初始位置

                         if (System.Windows.Input.Keyboard.Modifiers == ModifierKeys.Control && e.Key == Key.M)

                        {

                                textBox.SETVALue(Canvas.LeftProperty,0d);

                                textBox.SETVALue(Canvas.TopProperty,0d);

                        }

                }

        }

}