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

以下代码演示了如何使用WPF Thumb控件移动和调整大小Rectangle元素，并使用MVVMLight框架实现数据绑定。

首先，需要在XAML中定义Thumb和Rectangle元素，并将它们放置在Canvas中：

<Canvas>
    <Thumb x:Name="moveThumb" DragDelta="MoveThumb_DragDelta"/>
    <Thumb x:Name="resizeThumb" DragDelta="ResizeThumb_DragDelta"/>
    <Rectangle Width="{Binding Width}" Height="{Binding Height}" Fill="Blue"/>
</Canvas>

然后，在视图模型中定义Width，Height和Rotation属性，并使用PropertyChanged事件实现数据绑定：

public class MainViewModel : ViewModelBase
{
    private double _width = 100;
    private double _height = 100;
    private double _rotation = 0;

    public double Width
    {
        get { return _width; }
        set { Set(ref _width, value); }
    }

    public double Height
    {
        get { return _height; }
        set { Set(ref _height, value); }
    }

    public double Rotation
    {
        get { return _rotation; }
        set { Set(ref _rotation, value); }
    }

    // PropertyChanged event implementation
    public event PropertyChangedEventHandler PropertyChanged;

    protected virtual void OnPropertyChanged(string propertyName)
    {
        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
    }

    protected bool Set<T>(ref T storage, T value, [CallerMemberName] string propertyName = null)
    {
        if (Equals(storage, value)) return false;
        storage = value;
        OnPropertyChanged(propertyName);
        return true;
    }
}

在视图代码中，需要将Thumb元素与相应的操作连接起来：

public partial class MainWindow : Window
{
    public MainViewModel ViewModel { get; set; }

    public MainWindow()
    {
        InitializeComponent();
        DataContext = ViewModel = new MainViewModel();

        // Bind rectangle width and height to view model properties
        BindingOperations.SetBinding(Rectangle, WidthProperty, new Binding("Width") { Source = ViewModel });
        BindingOperations.SetBinding(Rectangle, HeightProperty, new Binding("Height") { Source = ViewModel });

        // Bind move thumb position to rectangle position
        BindingOperations.SetBinding(moveThumb, Canvas.LeftProperty, new Binding("Left") { Source = Rectangle });
        BindingOperations.SetBinding(moveThumb, Canvas.TopProperty, new Binding("Top") { Source = Rectangle });

        // Bind resize thumb position to rectangle right/bottom edges
        BindingOperations.SetBinding(resizeThumb, Canvas.LeftProperty, new Binding("Left") { Source = Rectangle, Converter = new AddValueConverter(), ConverterParameter = ViewModel.Width });
        BindingOperations.SetBinding(resizeThumb, Canvas.TopProperty, new Binding("Top") { Source = Rectangle, Converter = new AddValueConverter(), ConverterParameter = ViewModel.Height });
    }

    private void MoveThumb_DragDelta(object sender, DragDeltaEventArgs e)
    {
        ViewModel.Left += e.HorizontalChange;
        ViewModel.Top += e.VerticalChange;
    }

    private void ResizeThumb_DragDelta(object sender, DragDeltaEventArgs e)
    {
        ViewModel.Width += e.HorizontalChange;
        ViewModel.Height += e.VerticalChange;
    }
}

public class AddValueConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        if (value is double && parameter is double)
        {
            return (double)value + (double)parameter;
        }
        return value;
    }

    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        throw new NotImplementedException();
    }
}

这样，当用户拖动或调整大小Thumb时，视图模型中的相应属性将被更新，并且Rectangle元素将自动更新大小和位置。同时，可以使用MVVMLight框架的PropertyChanged事件实现数据绑定，从而避免了手动实现INotifyPropertyChanged接口的繁琐过程。