C# VisualStyleRenderer.GetBackgroundRegion方法代码示例

// Calculate and set the clipping region for the control  
// so that the corners of the title bar are rounded.
private void SetClipRegion()
{
    if (!Application.RenderWithVisualStyles)
    {
        return;
    }

    using (Graphics g = this.CreateGraphics())
    {
        // Get the current region for the window caption.
        if (SetRenderer(windowElements["windowCaption"]))
        {
            Region clipRegion = renderer.GetBackgroundRegion(
                g, elementRectangles["windowCaption"]);

            // Get the client rectangle, but exclude the region 
            // of the window caption.
            int height = (int)clipRegion.GetBounds(g).Height;
            Rectangle nonCaptionRect = new Rectangle(
                ClientRectangle.X,
                ClientRectangle.Y + height,
                ClientRectangle.Width,
                ClientRectangle.Height - height);

            // Add the rectangle to the caption region, and  
            // make this region the form's clipping region.
            clipRegion.Union(nonCaptionRect);
            this.Region = clipRegion;
        }
    }
}