WPF优化性能 - 爱码网

避免不必要地使用断字

除非需要，否则不建议使用自动断字功能。

画笔的不透明度与元素的不透明度

WPF创建临时曲面。

BitmapScalingMode

WPF染引擎在处理图像时从质量优化算法切换到速度优化算法。

// Set the bitmap scaling mode for the image to render faster.
RenderOptions.SetBitmapScalingMode(MyImage, BitmapScalingMode.LowQuality);

Image

WPF 加载缩略图大小的图像。

// Create Image Element
Image myImage = new Image();
myImage.Width = 200;

// Create source
BitmapImage myBitmapImage = new BitmapImage();

// BitmapImage.UriSource must be in a BeginInit/EndInit block
myBitmapImage.BeginInit();
myBitmapImage.UriSource = new Uri(@"C:\Documents and Settings\All Users\Documents\My Pictures\Sample Pictures\Water Lilies.jpg");

// To save significant application memory, set the DecodePixelWidth or
// DecodePixelHeight of the BitmapImage value of the image source to the desired
// height or width of the rendered image. If you don't do this, the application will
// cache the image as though it were rendered as its normal size rather then just
// the size that is displayed.
// Note: In order to preserve aspect ratio, set DecodePixelWidth
// or DecodePixelHeight but not both.
myBitmapImage.DecodePixelWidth = 200;
myBitmapImage.EndInit();
//set image source
myImage.Source = myBitmapImage;

StreamGeometry

PathGeometry对象相比，性能更好。

using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Media;
using System.Windows.Shapes;

namespace SDKSample
{
    // Use StreamGeometry with StreamGeometryContext to define a triangle shape.
    public partial class StreamGeometryTriangleExample : Page
    {
        public StreamGeometryTriangleExample()
        {
            // Create a path to draw a geometry with.
            Path myPath = new Path();
            myPath.Stroke = Brushes.Black;
            myPath.StrokeThickness = 1;

            // Create a StreamGeometry to use to specify myPath.
            StreamGeometry geometry = new StreamGeometry();
            geometry.FillRule = FillRule.EvenOdd;

            // Open a StreamGeometryContext that can be used to describe this StreamGeometry
            // object's contents.
            using (StreamGeometryContext ctx = geometry.Open())
            {

                // Begin the triangle at the point specified. Notice that the shape is set to
                // be closed so only two lines need to be specified below to make the triangle.
                ctx.BeginFigure(new Point(10, 100), true /* is filled */, true /* is closed */);

                // Draw a line to the next specified point.
                ctx.LineTo(new Point(100, 100), true /* is stroked */, false /* is smooth join */);

                // Draw another line to the next specified point.
                ctx.LineTo(new Point(100, 50), true /* is stroked */, false /* is smooth join */);
            }

            // Freeze the geometry (make it unmodifiable)
            // for additional performance benefits.
            geometry.Freeze();

            // Specify the shape (triangle) of the Path using the StreamGeometry.
            myPath.Data = geometry;

            // Add path shape to the UI.
            StackPanel mainPanel = new StackPanel();
            mainPanel.Children.Add(myPath);
            this.Content = mainPanel;
        }
    }
}

将 IList 绑定到 ItemsControl 而非 IEnumerable

IList<T>对象，这意味着您的性能受到第二个对象的不必要的开销的影响。

容器回收

Recycling 。

延迟滚动

在延迟滚动中，仅在用户释放滚动块时才会更新内容。

ScrollViewer 其控件模板中设置的任何控件上进行设置。

有关如何启用这些功能的信息，请参阅先前章节。

实现性能功能的控件
控制	虚拟化	容器回收	延迟滚动
ComboBox	可启用	可启用	可启用
ContextMenu	可启用	可启用	可启用
DocumentViewer	不可用	不可用	可启用
ListBox	默认	可启用	可启用
ListView	默认	可启用	可启用
TreeView	可启用	可启用	可启用
ToolBar	不可用	不可用	可启用