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Control.PointToScreen Method

Computes the location of the specified client point into screen coordinates.

Namespace: System.Windows.Forms
Assembly: System.Windows.Forms (in system.windows.forms.dll)

public:
Point PointToScreen (
	Point p
)
public Point PointToScreen (
	Point p
)
public function PointToScreen (
	p : Point
) : Point
Not applicable.

Parameters

p

The client coordinate Point to convert.

Return Value

A Point that represents the converted Point, 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.

private:
   // 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;
   Rectangle theRectangle;
   Point startPoint;
   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 = dynamic_cast<Control^>(sender);
      
      // Calculate the startPoint by using the PointToScreen 
      // method.
      startPoint = control->PointToScreen( Point(e->X,e->Y) );
   }

   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 )
      {
         ControlPaint::DrawReversibleFrame( theRectangle, this->BackColor, FrameStyle::Dashed );
         
         // Calculate the endpoint and dimensions for the new 
         // rectangle, again using the PointToScreen method.
         Point endPoint = this->PointToScreen( Point(e->X,e->Y) );
         int width = endPoint.X - startPoint.X;
         int height = endPoint.Y - startPoint.Y;
         theRectangle = Rectangle(startPoint.X,startPoint.Y,width,height);
         
         // Draw the new rectangle by calling DrawReversibleFrame
         // again.  
         ControlPaint::DrawReversibleFrame( theRectangle, this->BackColor, FrameStyle::Dashed );
      }
   }

   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.
      ControlPaint::DrawReversibleFrame( theRectangle, 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( Controls[ i ]->ClientRectangle );
         if ( controlRectangle.IntersectsWith( theRectangle ) )
         {
            Controls[ i ]->BackColor = Color::BurlyWood;
         }

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

// 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.
private boolean isDrag = false;
private Rectangle theRectangle =
    new Rectangle(new Point(0, 0), new Size(0, 0));
private 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.get_Button().Equals(MouseButtons.Left)) {
        isDrag = true;
    }

    Control control = (Control)sender;
    // Calculate the startPoint by using the PointToScreen 
    // method.
    startPoint = control.PointToScreen(new Point(e.get_X(), e.get_Y()));
} //Form1_MouseDown

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.
        ControlPaint.DrawReversibleFrame(theRectangle, this.get_BackColor(),
            FrameStyle.Dashed);
        // Calculate the endpoint and dimensions for the new 
        // rectangle, again using the PointToScreen method.
        Point endPoint = this.PointToScreen(new Point(e.get_X(), e.get_Y()));
        int width = endPoint.get_X() - startPoint.get_X();
        int height = endPoint.get_Y() - startPoint.get_Y();
        theRectangle = new Rectangle(startPoint.get_X(), startPoint.get_Y(),
            width, height);
        // Draw the new rectangle by calling DrawReversibleFrame
        // again.  
        ControlPaint.DrawReversibleFrame(theRectangle, this.get_BackColor(),
            FrameStyle.Dashed);
    }
} //Form1_MouseMove

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.
    ControlPaint.DrawReversibleFrame(theRectangle, this.get_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 < get_Controls().get_Count(); i++) {
        controlRectangle =
            get_Controls().get_Item(i).RectangleToScreen(get_Controls().
            get_Item(i).get_ClientRectangle());
        if (controlRectangle.IntersectsWith(theRectangle)) {
            get_Controls().get_Item(i).set_BackColor(Color.get_BurlyWood());
        }
    }
    // Reset the rectangle.
    theRectangle = new Rectangle(0, 0, 0, 0);
} //Form1_MouseUp

Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 2.0, 1.0

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