这里先封装一个方法,使用的时候先创建一个Draw,拿到DrawingContext 之后就可以通过DrawingContext 去绘制想要的图形,绘制完成后通过GetDraw拿到所有绘制的结果
添加一个PrintImage()用于测试当前绘图的样子用于测试
csharp
public class DrawVector
{
public DrawingVisual? visual { get; set; }
public DrawingContext CreateDraw()
{
if (visual == null)
visual = new DrawingVisual();
var dc = visual.RenderOpen();
return dc;
}
public DrawingGroup? GetDraw(DrawingContext? dc)
{
if (visual == null)
return null;
if (dc == null)
return null;
Dispose(dc);
var draw = visual.Drawing.Frozen();
//PrintImage();
return draw;
}
/// <summary>
/// 测试打印绘图结果
/// </summary>
private void PrintImage()
{
var bmp = new RenderTargetBitmap(2000, 2000, 96, 96, PixelFormats.Pbgra32);
bmp.Render(visual);
var encoder = new PngBitmapEncoder();
encoder.Frames.Add(BitmapFrame.Create(bmp));
using (var stream = new FileStream($"D:\\{Guid.NewGuid()}.png", FileMode.Create))
{
encoder.Save(stream);
}
}
public void RotationAngle(DrawingContext dc, Rect rect, double angleInDegrees)
{
var rotateTransform = new RotateTransform(angleInDegrees, rect.X + rect.Width / 2, rect.Y + rect.Height / 2);
dc.PushTransform(rotateTransform);
}
private void Dispose(DrawingContext? dc)
{
if (dc != null)
dc.Close();
}
}
使用实例
csharp
var drawVector = new DrawVector();
var dc = drawVector.CreateDraw();
dc.DrawRectangle(System.Windows.Media.Brushes.White, new System.Windows.Media.Pen(System.Windows.Media.Brushes.White, 1).Frozen(), new Rect(0, 0, MapBackCanvasWidth, MapBackCanvasHeight));
DrawVectorContent(dc);
return drawVector.GetDraw(dc);