WPF矩形 - 圆顶角

Question

如何才能让WPF矩形的顶角四舍五入？我创建了一个边框并设置了CornerRadius属性，在边框内我添加了我的矩形，但它不起作用，矩形没有圆角。

<Border BorderThickness="1" Grid.Row="0" Grid.ColumnSpan="2" CornerRadius="50,50,0,0" BorderBrush="Black">
    <Rectangle Fill="#FF5A9AE0" Grid.Row="0" Grid.ColumnSpan="2" Stretch="UniformToFill" ClipToBounds="True"/>
</Border>

Answer 1

你遇到的问题是矩形“溢出”边框的圆角。

矩形不能有单独的圆角，所以如果你只是将背景颜色放在边框上并删除矩形：

<Border BorderThickness="1" Grid.Row="0" Grid.ColumnSpan="2"
        CornerRadius="50,50,0,0" BorderBrush="Black" Background="#FF5A9AE0">
</Border>

你会得到你想要的效果。

Answer 2

在矩形上设置RadiusX和RadiusY属性，这将为其提供圆角

Answer 3

很好的例子，如何使用DrawingContext进行OnRender：

   /// <summary>
    /// Draws a rounded rectangle with four individual corner radius
    /// </summary>
    public static void DrawRoundedRectangle(this DrawingContext dc, Brush brush,
        Pen pen, Rect rect, CornerRadius cornerRadius)
    {
        var geometry = new StreamGeometry();
        using (var context = geometry.Open())
        {
            bool isStroked = pen != null;
            const bool isSmoothJoin = true;

            context.BeginFigure(rect.TopLeft + new Vector(0, cornerRadius.TopLeft), brush != null, true);
            context.ArcTo(new Point(rect.TopLeft.X + cornerRadius.TopLeft, rect.TopLeft.Y), 
                new Size(cornerRadius.TopLeft, cornerRadius.TopLeft),
                90, false, SweepDirection.Clockwise, isStroked, isSmoothJoin);
            context.LineTo(rect.TopRight - new Vector(cornerRadius.TopRight, 0), isStroked, isSmoothJoin);
            context.ArcTo(new Point(rect.TopRight.X, rect.TopRight.Y + cornerRadius.TopRight), 
                new Size(cornerRadius.TopRight, cornerRadius.TopRight),
                90, false, SweepDirection.Clockwise, isStroked, isSmoothJoin);
            context.LineTo(rect.BottomRight - new Vector(0, cornerRadius.BottomRight), isStroked, isSmoothJoin);
            context.ArcTo(new Point(rect.BottomRight.X - cornerRadius.BottomRight, rect.BottomRight.Y), 
                new Size(cornerRadius.BottomRight, cornerRadius.BottomRight),
                90, false, SweepDirection.Clockwise, isStroked, isSmoothJoin);
            context.LineTo(rect.BottomLeft + new Vector(cornerRadius.BottomLeft, 0), isStroked, isSmoothJoin);
            context.ArcTo(new Point(rect.BottomLeft.X, rect.BottomLeft.Y - cornerRadius.BottomLeft), 
                new Size(cornerRadius.BottomLeft, cornerRadius.BottomLeft),
                90, false, SweepDirection.Clockwise, isStroked, isSmoothJoin);

            context.Close();
        }
        dc.DrawGeometry(brush, pen, geometry);
    }

来自的信息： http://wpftutorial.net/DrawRoundedRectangle.html

Answer 4

即使使用Rectangle（或其他任何东西），它也能正常工作：

<Border>
    <Border.OpacityMask>
        <VisualBrush>
            <VisualBrush.Visual>
                <Border CornerRadius="5" Height="100" Width="100" Background="White"/>
            </VisualBrush.Visual>
        </VisualBrush>
    </Border.OpacityMask>

    // put your rounded content here

</Border>

如果您没有确切的内容大小，则必须使用高度和宽度。