C# Rectangle.Measure方法代码示例

        /// <summary>Creates the screenshot of entire plotter element</summary>
        /// <returns></returns>
        internal static BitmapSource CreateScreenshot(UIElement uiElement, Int32Rect screenshotSource)
        {
            Window window = Window.GetWindow(uiElement);
            if (window == null)
            {
                return CreateElementScreenshot(uiElement);
            }
            Size size = window.RenderSize;

            //double dpiCoeff = 32 / SystemParameters.CursorWidth;
            //int dpi = (int)(dpiCoeff * 96);
            double dpiCoeff = 1;
            int dpi = 96;

            RenderTargetBitmap bmp = new RenderTargetBitmap(
                (int)(size.Width * dpiCoeff), (int)(size.Height * dpiCoeff),
                dpi, dpi, PixelFormats.Default);

			// white background
			Rectangle whiteRect = new Rectangle { Width = size.Width, Height = size.Height, Fill = Brushes.White };
			whiteRect.Measure(size);
			whiteRect.Arrange(new Rect(size));
			bmp.Render(whiteRect);
			// the very element
            bmp.Render(uiElement);

            CroppedBitmap croppedBmp = new CroppedBitmap(bmp, screenshotSource);
            return croppedBmp;
        }

		public void MeasureTest1 ()
		{
			Rectangle r = new Rectangle ();
			r.Width = 10;
			r.Height = 20;

			r.Measure (new Size (50, 50));

			Assert.AreEqual (new Size (0, 0), r.DesiredSize);
		}

		public void MeasureTest2 ()
		{
			Canvas c = new Canvas ();
			Rectangle r = new Rectangle ();
			r.Width = 10;
			r.Height = 20;

			r.Measure (new Size (50, 50));
			Assert.AreEqual (new Size (0, 0), r.DesiredSize);
			
			c.Children.Add (r);

			r.Measure (new Size (50, 50));
			Assert.AreEqual (new Size (0, 0), r.DesiredSize);

			c.Measure (new Size (50, 50));

			Assert.AreEqual (new Size (0, 0), c.DesiredSize, "Canvas desired");
			Assert.AreEqual (new Size (0, 0), r.DesiredSize, "Rectangle desired");
		}

		public void MeasureTest3 ()
		{
			Border c = new Border ();
			Rectangle r = new Rectangle ();
			r.Width = 10;
			r.Height = 20;

			r.Measure (new Size (50, 50));

			Assert.AreEqual (new Size (0, 0), r.DesiredSize);
			
			c.Child = r;
			c.Measure (new Size (50, 50));

			Assert.AreEqual (new Size (10, 20), c.DesiredSize, "Border desired");
			Assert.AreEqual (new Size (10, 20), r.DesiredSize, "Rectangle desired");
		}

		public void MeasureTest2_1 ()
		{
			Border b = new Border ();
			Canvas c = new Canvas ();
			Rectangle r = new Rectangle ();
			r.Width = 10;
			r.Height = 20;

			r.Measure (new Size (50, 50));
			Assert.AreEqual (new Size (0, 0), r.DesiredSize);

			b.Child = c;
			c.Children.Add (r);

			b.Width = 20;
			b.Height = 10;
			b.Measure (new Size (50, 50));
			Assert.AreEqual (new Size (0, 0), c.DesiredSize, "Canvas desired");
			Assert.AreEqual (new Size (0, 0), r.DesiredSize, "Rectangle desired");
			Assert.AreEqual (new Size (20, 10), b.DesiredSize, "Border desired");
		}

        static void Apply(Shader shader, BitmapImage bitmap, string destImage)
        {
            Rectangle r = new Rectangle ();
            r.Effect = shader;
            shader.Input = new ImageBrush (bitmap);
            /*The fill brush is ignored due to the effect been applied*/
            r.Fill = new SolidColorBrush (Colors.Aquamarine);

            Size size = new Size (bitmap.PixelWidth, bitmap.PixelHeight);
            r.Measure (size);
            r.Arrange (new Rect (size));

            RenderTargetBitmap render = new RenderTargetBitmap (
                bitmap.PixelWidth,
                bitmap.PixelHeight,
                96,
                96,
                PixelFormats.Pbgra32);

            render.Render (r);

            PngBitmapEncoder png = new PngBitmapEncoder ();
            png.Frames.Add (BitmapFrame.Create (render));
            using (Stream stm = File.Open (destImage, FileMode.OpenOrCreate)) {
                png.Save (stm);
            }
        }

        protected override void CreateHeatMap()
        {
            intensityMap = new RenderTargetBitmap(500, 500, 96, 96, PixelFormats.Pbgra32);
            AddativeBlendClear cleareffect = new AddativeBlendClear();
            cleareffect.ClearColor = Color.FromArgb(0x01, 0xFF, 0xFF, 0xFF);

            ClearIntensityMap();
            Size sz = new Size(intensityMap.PixelWidth, intensityMap.PixelHeight);

            // Create the clear rectangle, we need this to render a fade pass.
            clearRectangle = new Rectangle();
            clearRectangle.Fill = new ImageBrush(intensityMap);
            clearRectangle.Effect = cleareffect;
            clearRectangle.Measure(sz);
            clearRectangle.Arrange(new Rect(sz));

            // Connect the intensity map containing our heat to our image.
            HeatMapImage.Source = intensityMap;
        }

        private static BitmapSource CreateElementScreenshot(UIElement uiElement)
        {
            bool measureValid = uiElement.IsMeasureValid;

            if (!measureValid)
            {
                double width = 300;
                double height = 300;

                FrameworkElement frElement = uiElement as FrameworkElement;
                if (frElement != null)
                {
                    if (!Double.IsNaN(frElement.Width))
                        width = frElement.Width;
                    if (!Double.IsNaN(frElement.Height))
                        height = frElement.Height;
                }

                Size size = new Size(width, height);
                uiElement.Measure(size);
                uiElement.Arrange(new Rect(size));
            }

            RenderTargetBitmap bmp = new RenderTargetBitmap(
                (int)uiElement.RenderSize.Width, (int)uiElement.RenderSize.Height,
                96, 96, PixelFormats.Default);

            // this is waiting for dispatcher to perform measure, arrange and render passes
            uiElement.Dispatcher.Invoke(((Action)(() => { })), DispatcherPriority.Background);

			Size elementSize = uiElement.DesiredSize;
			// white background
			Rectangle whiteRect = new Rectangle { Width = elementSize.Width, Height = elementSize.Height, Fill = Brushes.White };
			whiteRect.Measure(elementSize);
			whiteRect.Arrange(new Rect(elementSize));
			bmp.Render(whiteRect);

            bmp.Render(uiElement);

            return bmp;
        }

 public SquaredArrow()
 {
     Rectangle r = new Rectangle();
     r.Measure(new Size(100, 100));
     r.Arrange(new Rect(0, 0, 100, 100));
 }