Control.RectangleToScreen Method (Rectangle)


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Computes the size and location of the specified client rectangle in screen coordinates.

Namespace:   System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

public Rectangle RectangleToScreen(
	Rectangle r


Type: System.Drawing.Rectangle

The client coordinate Rectangle to convert.

Return Value

Type: System.Drawing.Rectangle

A Rectangle that represents the converted Rectangle, p, in screen coordinates.

The following code example demonstrates how to use the BackColor, RectangleToScreen, PointToScreen, MouseButtons, ControlPaint.DrawReversibleFrame, and Rectangle.IntersectsWith members. To run the example, paste the following code in a form called Form1 containing several controls. This example requires that the MouseDown, MouseMove, and MouseUp events are connected to the event handlers defined in the example.

  // The following three methods will draw a rectangle and allow 
  // the user to use the mouse to resize the rectangle.  If the 
  // rectangle intersects a control's client rectangle, the 
  // control's color will change.

  bool isDrag = false;
  Rectangle theRectangle = new Rectangle
(new Point(0, 0), new Size(0, 0));
  Point startPoint;

  private void Form1_MouseDown(object sender, 
System.Windows.Forms.MouseEventArgs e)

      // Set the isDrag variable to true and get the starting point 
      // by using the PointToScreen method to convert form 
// coordinates to screen coordinates.
      if (e.Button==MouseButtons.Left)
          isDrag = true;

      Control control = (Control) sender;

      // Calculate the startPoint by using the PointToScreen 
      // method.
      startPoint = control.PointToScreen(new Point(e.X, e.Y));

  private void Form1_MouseMove(object sender, 
System.Windows.Forms.MouseEventArgs e)

      // If the mouse is being dragged, 
// undraw and redraw the rectangle as the mouse moves.
      if (isDrag)

          // Hide the previous rectangle by calling the 
	// DrawReversibleFrame method with the same parameters.
		this.BackColor, FrameStyle.Dashed);

          // Calculate the endpoint and dimensions for the new 
       // rectangle, again using the PointToScreen method.
          Point endPoint = ((Control) sender).PointToScreen(new Point(e.X, e.Y));

          int width = endPoint.X-startPoint.X;
          int height = endPoint.Y-startPoint.Y;
          theRectangle = new Rectangle(startPoint.X, 
		startPoint.Y, width, height);

          // Draw the new rectangle by calling DrawReversibleFrame
	// again.  
		this.BackColor, FrameStyle.Dashed);

  private void Form1_MouseUp(object sender, 
System.Windows.Forms.MouseEventArgs e)

      // If the MouseUp event occurs, the user is not dragging.
      isDrag = false;

      // Draw the rectangle to be evaluated. Set a dashed frame style 
      // using the FrameStyle enumeration.
	this.BackColor, FrameStyle.Dashed);

      // Find out which controls intersect the rectangle and 
      // change their color. The method uses the RectangleToScreen  
      // method to convert the Control's client coordinates 
// to screen coordinates.
   Rectangle controlRectangle;
      for(int i = 0; i < Controls.Count; i++)
          controlRectangle = Controls[i].RectangleToScreen
          if (controlRectangle.IntersectsWith(theRectangle))
              Controls[i].BackColor = Color.BurlyWood;

      // Reset the rectangle.
      theRectangle = new Rectangle(0, 0, 0, 0);

.NET Framework
Available since 1.1
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