WPF Thumb 移动rectangle改变rectangle大小，旋转 rectangle mvvmlight提供实现代码

好的，下面是一个简单的代码示例，演示了如何使用 WPF Thumb 控件实现拖动、改变大小和旋转矩形，以及如何使用 MVVMLight 框架来实现数据绑定。该示例中，我们使用了一个名为 RectangleViewModel 的 ViewModel 类来管理矩形的属性。 XAML 代码： ``` <Window x:Class="WpfApp1.MainWindow" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:local="clr-namespace:WpfApp1" Title="MainWindow" Height="450" Width="800"> <Window.DataContext> <local:RectangleViewModel/> </Window.DataContext> <Canvas> <!-- 矩形 --> <Rectangle Width="{Binding Width}" Height="{Binding Height}" Fill="LightBlue" Canvas.Left="{Binding X}" Canvas.Top="{Binding Y}"> <Rectangle.RenderTransform> <RotateTransform Angle="{Binding Angle}" CenterX="0.5" CenterY="0.5"/> </Rectangle.RenderTransform> </Rectangle> <!-- 拖动 Thumb --> <Thumb Canvas.Left="{Binding X}" Canvas.Top="{Binding Y}" Width="10" Height="10" DragDelta="Thumb_DragDelta"/> <!-- 上边缘改变大小 Thumb --> <Thumb Canvas.Left="{Binding X}" Canvas.Top="{Binding Y}" Width="10" Height="10" Cursor="SizeNS" DragDelta="ResizeTop_DragDelta"/> <!-- 下边缘改变大小 Thumb --> <Thumb Canvas.Left="{Binding X}" Canvas.Top="{Binding Y}" Width="10" Height="10" Cursor="SizeNS" DragDelta="ResizeBottom_DragDelta"/> <!-- 左边缘改变大小 Thumb --> <Thumb Canvas.Left="{Binding X}" Canvas.Top="{Binding Y}" Width="10" Height="10" Cursor="SizeWE" DragDelta="ResizeLeft_DragDelta"/> <!-- 右边缘改变大小 Thumb --> <Thumb Canvas.Left="{Binding X}" Canvas.Top="{Binding Y}" Width="10" Height="10" Cursor="SizeWE" DragDelta="ResizeRight_DragDelta"/> <!-- 左上角改变大小 Thumb --> <Thumb Canvas.Left="{Binding X}" Canvas.Top="{Binding Y}" Width="10" Height="10" Cursor="SizeNWSE" DragDelta="ResizeTopLeft_DragDelta"/> <!-- 右上角改变大小 Thumb --> <Thumb Canvas.Left="{Binding X}" Canvas.Top="{Binding Y}" Width="10" Height="10" Cursor="SizeNESW" DragDelta="ResizeTopRight_DragDelta"/> <!-- 左下角改变大小 Thumb --> <Thumb Canvas.Left="{Binding X}" Canvas.Top="{Binding Y}" Width="10" Height="10" Cursor="SizeNESW" DragDelta="ResizeBottomLeft_DragDelta"/> <!-- 右下角改变大小 Thumb --> <Thumb Canvas.Left="{Binding X}" Canvas.Top="{Binding Y}" Width="10" Height="10" Cursor="SizeNWSE" DragDelta="ResizeBottomRight_DragDelta"/> <!-- 旋转 Thumb --> <Thumb Canvas.Left="{Binding X}" Canvas.Top="{Binding Y}" Width="10" Height="10" Cursor="Hand" DragDelta="Rotate_DragDelta"/> </Canvas> </Window> ``` C# 代码： ``` using System.Windows; using System.Windows.Controls; using System.Windows.Input; using System.Windows.Media; namespace WpfApp1 { public partial class MainWindow : Window { public MainWindow() { InitializeComponent(); } private void Thumb_DragDelta(object sender, DragDeltaEventArgs e) { RectangleViewModel viewModel = DataContext as RectangleViewModel; viewModel.X += e.HorizontalChange; viewModel.Y += e.VerticalChange; } private void ResizeTop_DragDelta(object sender, DragDeltaEventArgs e) { RectangleViewModel viewModel = DataContext as RectangleViewModel; viewModel.Y += e.VerticalChange; viewModel.Height -= e.VerticalChange; } private void ResizeBottom_DragDelta(object sender, DragDeltaEventArgs e) { RectangleViewModel viewModel = DataContext as RectangleViewModel; viewModel.Height += e.VerticalChange; } private void ResizeLeft_DragDelta(object sender, DragDeltaEventArgs e) { RectangleViewModel viewModel = DataContext as RectangleViewModel; viewModel.X += e.HorizontalChange; viewModel.Width -= e.HorizontalChange; } private void ResizeRight_DragDelta(object sender, DragDeltaEventArgs e) { RectangleViewModel viewModel = DataContext as RectangleViewModel; viewModel.Width += e.HorizontalChange; } private void ResizeTopLeft_DragDelta(object sender, DragDeltaEventArgs e) { RectangleViewModel viewModel = DataContext as RectangleViewModel; viewModel.X += e.HorizontalChange; viewModel.Width -= e.HorizontalChange; viewModel.Y += e.VerticalChange; viewModel.Height -= e.VerticalChange; } private void ResizeTopRight_DragDelta(object sender, DragDeltaEventArgs e) { RectangleViewModel viewModel = DataContext as RectangleViewModel; viewModel.Width += e.HorizontalChange; viewModel.Y += e.VerticalChange; viewModel.Height -= e.VerticalChange; } private void ResizeBottomLeft_DragDelta(object sender, DragDeltaEventArgs e) { RectangleViewModel viewModel = DataContext as RectangleViewModel; viewModel.X += e.HorizontalChange; viewModel.Width -= e.HorizontalChange; viewModel.Height += e.VerticalChange; } private void ResizeBottomRight_DragDelta(object sender, DragDeltaEventArgs e) { RectangleViewModel viewModel = DataContext as RectangleViewModel; viewModel.Width += e.HorizontalChange; viewModel.Height += e.VerticalChange; } private void Rotate_DragDelta(object sender, DragDeltaEventArgs e) { RectangleViewModel viewModel = DataContext as RectangleViewModel; double centerX = viewModel.X + viewModel.Width / 2; double centerY = viewModel.Y + viewModel.Height / 2; Point mousePoint = Mouse.GetPosition(this); Point centerPoint = new Point(centerX, centerY); double angle = Math.Atan2(mousePoint.Y - centerPoint.Y, mousePoint.X - centerPoint.X) * 180 / Math.PI; viewModel.Angle = angle; } } public class RectangleViewModel : ViewModelBase { private double _x; public double X { get { return _x; } set { if (_x != value) { _x = value; RaisePropertyChanged("X"); } } } private double _y; public double Y { get { return _y; } set { if (_y != value) { _y = value; RaisePropertyChanged("Y"); } } } private double _width = 100; public double Width { get { return _width; } set { if (_width != value) { _width = value; RaisePropertyChanged("Width"); } } } private double _height = 100; public double Height { get { return _height; } set { if (_height != value) { _height = value; RaisePropertyChanged("Height"); } } } private double _angle; public double Angle { get { return _angle; } set { if (_angle != value) { _angle = value; RaisePropertyChanged("Angle"); } } } } public class ViewModelBase : System.ComponentModel.INotifyPropertyChanged { public event System.ComponentModel.PropertyChangedEventHandler PropertyChanged; protected void RaisePropertyChanged(string propertyName) { PropertyChanged?.Invoke(this, new System.ComponentModel.PropertyChangedEventArgs(propertyName)); } } } ``` 这个示例演示了如何使用 WPF Thumb 控件实现矩形的拖动、改变大小和旋转，以及如何使用 MVVMLight 框架实现数据绑定。请注意，这只是一个简单的示例，可以根据您的需要进行修改和扩展。