C#WPF OnPaint方法替代？

DrawingVisual visual = new DrawingVisual();
using (DrawingContext context = visual.RenderOpen())
{
    context.DrawRectangle(Brushes.Red, null, new Rect(new Point(0, 0), new Size(100, 100)));
}

// 将DrawingVisual对象添加到UIElement的VisualChildren集合中
UIElement.AddVisualChild(visual);

// 在XAML中使用Path控件进行绘制
<Path Stroke="Red" StrokeThickness="2" Data="M 0,0 L 100,100" />

// 在代码中使用Path控件进行绘制
Path path = new Path();
path.Stroke = Brushes.Red;
path.StrokeThickness = 2;
path.Data = Geometry.Parse("M 0,0 L 100,100");

WriteableBitmap bitmap = new WriteableBitmap(200, 200, 96, 96, PixelFormats.Pbgra32, null);
bitmap.Lock();
IntPtr ptr = bitmap.BackBuffer;

// 在位图上绘制图形
// ...

bitmap.AddDirtyRect(new Int32Rect(0, 0, 200, 200));
bitmap.Unlock();

// 将位图显示在UI上
Image image = new Image();
image.Source = bitmap;