How Draw rectangle in WPF?

Question

I need draw rectangle in canvas. I know how to draw. But I did not get to do so would draw on a 360-degree

Example. blue, lilac, green they are one and the same rect

Answer 1

You don't really need to rotate as such - just adjust the height, width, and top-left of your rectangle based on your mouse position.

This is probably a good starting point for you:

XAML:

Code Behind:

    private bool _mouseDown = false;
    private Rectangle _current;
    private Point _initialPoint;

    private void Canvas_MouseDown(object sender, MouseButtonEventArgs e)
    {
        _mouseDown = (e.ButtonState == MouseButtonState.Pressed) 
                                     && (e.ChangedButton == MouseButton.Left);
        if (!_mouseDown)
            return;

        _current = new Rectangle();
        _initialPoint = e.MouseDevice.GetPosition(MyCanvas);
        _current.Fill = new SolidColorBrush(Colors.Blue);
        MyCanvas.Children.Add(_current);
    }
    private void Canvas_MouseMove(object sender, MouseEventArgs e)
    {
        if (!_mouseDown)
            return;

        Point position = e.MouseDevice.GetPosition(MyCanvas);
        _current.SetValue(Canvas.LeftProperty,
                                         Math.Min(position.X, _initialPoint.X));
        _current.SetValue(Canvas.TopProperty,
                                         Math.Min(position.Y, _initialPoint.Y));
        _current.Width = Math.Abs(position.X - _initialPoint.X);
        _current.Height = Math.Abs(position.Y - _initialPoint.Y);
          }
    private void Canvas_MouseUp(object sender, MouseButtonEventArgs e)
    {
        if (e.ChangedButton == MouseButton.Left)
            _mouseDown = false;
    }