ControlPaint.DrawReversibleLine(Point, Point, Color) Metod

public:
 static void DrawReversibleLine(System::Drawing::Point start, System::Drawing::Point end, System::Drawing::Color backColor);

public static void DrawReversibleLine(System.Drawing.Point start, System.Drawing.Point end, System.Drawing.Color backColor);

static member DrawReversibleLine : System.Drawing.Point * System.Drawing.Point * System.Drawing.Color -> unit

Public Shared Sub DrawReversibleLine (start As Point, end As Point, backColor As Color)

Parametrar

Exempel

Följande kodexempel visar hur du ControlPaint.DrawReversibleLine använder metoderna och Control.PointToScreen . Om du vill köra exemplet klistrar du in följande kod i ett formulär. Lägg till en knapp med namnet Button3 i formuläret och se till att alla händelser är anslutna till deras händelsehanterare.

// When the mouse hovers over Button3, two reversible lines are 
// drawn using the corner coordinates of Button3, which are first 
// converted to screen coordinates.
void Button3_MouseHover( Object^ /*sender*/, System::EventArgs^ /*e*/ )
{
   ControlPaint::DrawReversibleLine( Button3->PointToScreen( Point(0,0) ), Button3->PointToScreen( Point(Button3->ClientRectangle.Right,Button3->ClientRectangle.Bottom) ), SystemColors::Control );
   ControlPaint::DrawReversibleLine( Button3->PointToScreen( Point(Button3->ClientRectangle.Right,Button3->ClientRectangle.Top) ), Button3->PointToScreen( Point(Button1->ClientRectangle.Left,Button3->ClientRectangle.Bottom) ), SystemColors::Control );
}

// When the mouse moves from Button3, the reversible lines are erased by
// using the same coordinates as are used in the Button3_MouseHover method.
void Button3_MouseLeave( Object^ /*sender*/, System::EventArgs^ /*e*/ )
{
   ControlPaint::DrawReversibleLine( Button3->PointToScreen( Point(0,0) ), Button3->PointToScreen( Point(Button3->ClientRectangle.Right,Button3->ClientRectangle.Bottom) ), SystemColors::Control );
   ControlPaint::DrawReversibleLine( Button3->PointToScreen( Point(Button3->ClientRectangle.Right,Button3->ClientRectangle.Top) ), Button3->PointToScreen( Point(Button3->ClientRectangle.Left,Button3->ClientRectangle.Bottom) ), SystemColors::Control );
}

// When the mouse hovers over Button3, two reversible lines are 
// drawn using the corner coordinates of Button3, which are first 
// converted to screen coordinates.
private void Button3_MouseHover(object sender, System.EventArgs e)
{
    ControlPaint.DrawReversibleLine(Button3.PointToScreen(
        new Point(0, 0)), Button3.PointToScreen(
        new Point(Button3.ClientRectangle.Right, 
        Button3.ClientRectangle.Bottom)), SystemColors.Control);
    
    ControlPaint.DrawReversibleLine(Button3.PointToScreen(
        new Point(Button3.ClientRectangle.Right, 
        Button3.ClientRectangle.Top)), 
        Button3.PointToScreen(new Point(Button1.ClientRectangle.Left, 
        Button3.ClientRectangle.Bottom)), SystemColors.Control);
}

// When the mouse moves from Button3, the reversible lines are erased by
// using the same coordinates as are used in the Button3_MouseHover method.
private void Button3_MouseLeave(object sender, System.EventArgs e)
{
    ControlPaint.DrawReversibleLine(Button3.PointToScreen(
        new Point(0, 0)), Button3.PointToScreen(
        new Point(Button3.ClientRectangle.Right, 
        Button3.ClientRectangle.Bottom)), SystemColors.Control);
    
    ControlPaint.DrawReversibleLine(Button3.PointToScreen(
        new Point(Button3.ClientRectangle.Right, 
        Button3.ClientRectangle.Top)), 
        Button3.PointToScreen(new Point(Button3.ClientRectangle.Left,
        Button3.ClientRectangle.Bottom)), SystemColors.Control);
}

' When the mouse hovers over Button3, two reversible lines are drawn
' using the corner coordinates of Button3, which are first 
' converted to screen coordinates.
Private Sub Button3_MouseHover(ByVal sender As Object, _
    ByVal e As System.EventArgs) Handles Button3.MouseHover

    ControlPaint.DrawReversibleLine(Button3.PointToScreen(New Point(0, 0)), _
    Button3.PointToScreen(New Point(Button3.ClientRectangle.Right, _
        Button3.ClientRectangle.Bottom)), SystemColors.Control)
    ControlPaint.DrawReversibleLine(Button3.PointToScreen( _
        New Point(Button3.ClientRectangle.Right, Button3.ClientRectangle.Top)), _
       Button3.PointToScreen(New Point _
            (Button1.ClientRectangle.Left, Button3.ClientRectangle.Bottom)), _
            SystemColors.Control)
End Sub

' When the mouse moves from Button3, the reversible lines are 
' erased by using the same coordinates as are used in the
' Button3_MouseHover method.
Private Sub Button3_MouseLeave(ByVal sender As Object, _
    ByVal e As System.EventArgs) Handles Button3.MouseLeave

    ControlPaint.DrawReversibleLine(Button3.PointToScreen(New Point(0, 0)), _
    Button3.PointToScreen(New Point(Button3.ClientRectangle.Right, _
        Button3.ClientRectangle.Bottom)), SystemColors.Control)
    ControlPaint.DrawReversibleLine(Button3.PointToScreen( _
        New Point(Button3.ClientRectangle.Right, Button3.ClientRectangle.Top)), _
       Button3.PointToScreen(New Point(Button3.ClientRectangle.Left, _
       Button3.ClientRectangle.Bottom)), SystemColors.Control)
End Sub

Kommentarer

Parametern backColor används för att beräkna radens fyllningsfärg så att den alltid visas mot bakgrunden.

Resultatet av den här metoden kan vändas genom att rita samma linje igen. Att rita en linje med den här metoden liknar att invertera en region på skärmen, förutom att den ger bättre prestanda för en bredare mängd olika färger.

Se även

• FrameStyle