ControlPaint.DrawReversibleFrame(Rectangle, Color, FrameStyle) ControlPaint.DrawReversibleFrame(Rectangle, Color, FrameStyle) ControlPaint.DrawReversibleFrame(Rectangle, Color, FrameStyle) Method

定义

在屏幕上的指定边界内,按指定背景色绘制处于指定状态的可逆框架。Draws a reversible frame on the screen within the specified bounds, with the specified background color, and in the specified state.

public:
 static void DrawReversibleFrame(System::Drawing::Rectangle rectangle, System::Drawing::Color backColor, System::Windows::Forms::FrameStyle style);
public static void DrawReversibleFrame (System.Drawing.Rectangle rectangle, System.Drawing.Color backColor, System.Windows.Forms.FrameStyle style);
static member DrawReversibleFrame : System.Drawing.Rectangle * System.Drawing.Color * System.Windows.Forms.FrameStyle -> unit

参数

rectangle
Rectangle Rectangle Rectangle

代表要绘制矩形的尺寸的 Rectangle(采用屏幕坐标)。The Rectangle that represents the dimensions of the rectangle to draw, in screen coordinates.

backColor
Color Color Color

框架的背景的 ColorThe Color of the background behind the frame.

style
FrameStyle FrameStyle FrameStyle

FrameStyle 值之一,它指定框架的样式。One of the FrameStyle values that specifies the style of the frame.

示例

下面的代码示例演示如何使用Control.RectangleToScreenControl.PointToScreenDrawReversibleFrame成员。The following code example demonstrates how to use the Control.RectangleToScreen, Control.PointToScreen, and the DrawReversibleFrame members. 若要运行该示例, 请将以下代码粘贴到一个Form1名为的窗体中, 其中包含多个控件。To run the example, paste the following code in a form called Form1 containing several controls. 此示例要求鼠标事件连接到在示例中定义的事件处理程序。This example requires that the mouse 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.

  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 = ((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.  
          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);
  }
' 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 = CType(sender, Control).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

注解

backColor参数用于计算框架的填充颜色, 使其在背景上始终可见。The backColor parameter is used to calculate the fill color of the frame so that it is always visible against the background.

再次绘制同一帧可以反转此方法的结果。The results of this method can be reversed by drawing the same frame again. 使用此方法绘制帧类似于反转屏幕的区域, 只不过它可以为各种颜色提供更好的性能。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.

适用于

另请参阅