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ControlPaint.DrawReversibleFrame Method

Draws a reversible frame on the screen within the specified bounds, with the specified background color, and in the specified state.

[Visual Basic]
Public Shared Sub DrawReversibleFrame( _
   ByVal rectangle As Rectangle, _
   ByVal backColor As Color, _
   ByVal style As FrameStyle _
)
[C#]
public static void DrawReversibleFrame(
 Rectangle rectangle,
 Color backColor,
 FrameStyle style
);
[C++]
public: static void DrawReversibleFrame(
 Rectangle rectangle,
 Color backColor,
 FrameStyle style
);
[JScript]
public static function DrawReversibleFrame(
   rectangle : Rectangle,
 backColor : Color,
 style : FrameStyle
);

Parameters

rectangle
The Rectangle that represents the dimensions of the rectangle to draw, in screen coordinates.
backColor
The Color of the background behind the frame.
style
One of the FrameStyle values that specifies the style of the frame.

Remarks

The backColor parameter is used to calculate the fill color of the frame so that it is always visible against the background.

The results of this method can be reversed by drawing the same frame again. Drawing a frame using this method is similar to inverting a region of the screen, except that it provides better performance for a wider variety of colors.

Example

[Visual Basic, C#] The following code example demonstrates how to use the BackColor, RectangleToScreen, PointToScreen, DrawReversibleFrame, and IntersectsWith members. To run the example, paste the following code in a form called Form1 containing several controls. This example assumes the MouseDown, MouseMove, and MouseUp events are connected to the event handling methods defined in the example.

[Visual Basic] 
' 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.

Dim isDrag As Boolean = False
Dim theRectangle As New rectangle(New Point(0, 0), New Size(0, 0))
Dim startPoint As Point

Private Sub Form1_MouseDown(ByVal sender As Object, ByVal e As _
    System.Windows.Forms.MouseEventArgs) Handles MyBase.MouseDown

    ' 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) Then
        isDrag = True
    End If

    Dim control As Control = CType(sender, Control)

    ' Calculate the startPoint by using the PointToScreen 
    ' method.
    startPoint = control.PointToScreen(New Point(e.X, e.Y))
End Sub

Private Sub Form1_MouseMove(ByVal sender As Object, ByVal e As _
System.Windows.Forms.MouseEventArgs) Handles MyBase.MouseMove

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

        ' Hide the previous rectangle by calling the DrawReversibleFrame 
        ' method with the same parameters.
        ControlPaint.DrawReversibleFrame(theRectangle, Me.BackColor, _
            FrameStyle.Dashed)

        ' Calculate the endpoint and dimensions for the new rectangle, 
        ' again using the PointToScreen method.
        Dim endPoint As Point = Me.PointToScreen(New Point(e.X, e.Y))
        Dim width As Integer = endPoint.X - startPoint.X
        Dim height As Integer = endPoint.Y - startPoint.Y
        theRectangle = New Rectangle(startPoint.X, startPoint.Y, _
            width, height)

        ' Draw the new rectangle by calling DrawReversibleFrame again.  
        ControlPaint.DrawReversibleFrame(theRectangle, Me.BackColor, _
             FrameStyle.Dashed)
    End If
End Sub

Private Sub Form1_MouseUp(ByVal sender As Object, ByVal e As _
System.Windows.Forms.MouseEventArgs) Handles MyBase.MouseUp

    ' 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, Me.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.
    Dim i As Integer
    Dim controlRectangle As Rectangle
    For i = 0 To Controls.Count - 1
        controlRectangle = Controls(i).RectangleToScreen _
            (Controls(i).ClientRectangle)
        If controlRectangle.IntersectsWith(theRectangle) Then
            Controls(i).BackColor = Color.BurlyWood
        End If
    Next

    ' Reset the rectangle.
    theRectangle = New Rectangle(0, 0, 0, 0)
End Sub

[C#] 
// 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.
    {
        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(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.  
        ControlPaint.DrawReversibleFrame(theRectangle, 
            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.
    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 = new Rectangle(0, 0, 0, 0);
}

[C++, JScript] No example is available for C++ or JScript. To view a Visual Basic or C# example, click the Language Filter button Language Filter in the upper-left corner of the page.

Requirements

Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family

See Also

ControlPaint Class | ControlPaint Members | System.Windows.Forms Namespace | FrameStyle

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