0

我想在 Windows 窗体上绘制许多不同的形状。以下代码仅适用于矩形。

// render list contains all shapes
List<Rectangle> DrawList = new List<Rectangle>();

// add example data
DrawList.Add(new Rectangle(10, 30, 10, 40));
DrawList.Add(new Rectangle(20, 10, 20, 10));
DrawList.Add(new Rectangle(10, 20, 30, 20));

// draw
private void Form1_Paint(object sender, PaintEventArgs e)
{
    Graphics g = e.Graphics;
    foreach (Rectangle Object in DrawList)
    {
        g.FillRectangle(new SolidBrush(Color.Black), Object);
    } 
}

如何改进代码以处理任何类型的形状，如矩形、直线、曲线等？

我想我需要一个可以包含不同类型对象的列表和一个根据其形状类型绘制任何对象的函数。但不幸的是，我不知道该怎么做。

4

1 回答 1

5

像这样的东西：

public abstract class MyShape
{
   public abstract void Draw(PaintEventArgs args);
}

public class MyRectangle : MyShape
{
    public int Height { get; set; }
    public int Width { get;set; }
    public int X { get; set; }
    public int Y { get; set; }

    public override void Draw(Graphics graphics)
    {
        graphics.FillRectangle(
            new SolidBrush(Color.Black),
            new Rectangle(X, Y, Width, Height));
    }
}

public class MyCircle : MyShape
{
    public int Radius { get; set; }
    public int X { get; set; }
    public int Y { get; set; }

    public override void Draw(Graphics graphics)
    {
        /* drawing code here */
    }        
}

private void Form1_Paint(object sender, PaintEventArgs e)
{
    List<MyShape> toDraw = new List<MyShape> 
    {
        new MyRectangle
        {
            Height = 10,
            Width: 20,
            X = 0,
            Y = 0
        },
        new MyCircle
        {
           Radius = 5,
           X = 5,
           Y = 5
        }
    };

    toDraw.ForEach(s => s.Draw(e.Graphics));
}

或者，您可以为要绘制的每种类型创建一个扩展方法。例子：

public static class ShapeExtensions
{
    public static void Draw(this Rectangle r, Graphics graphics)
    {
        graphics.FillRectangle(new SolidBrush(Color.Black), r);
    }
}
于 2012-07-29T10:24:17.883 回答