用另一种方法画图class

Question

我想用另一个Class中的方法画一个圆。但是它在我的 class 中的第 41 行和第 42 行显示 无效参数。当我完成这个项目时，它应该是一个模拟时钟。这是我的第一个项目，我正在画画 Event.Im 看不懂，不知道如何解决我的问题。我是表格的新手。我已经尝试在主体中绘制圆圈并且它工作正常但是它没有放入 class。对不起，我的 class 名字可能看起来很奇怪，因为我是德国人。感谢您的帮助。

那是我的 class:

    class Ziffernblatt
    {
        Size RectSize;

        Point RectPoint = new Point(5, 10);

        Rectangle Myrect;
        Rectangle MyCircle;

        Pen MyPen = new Pen(Color.Black, 1);
        Pen Invpen = new Pen(Color.White, 1);

        Graphics gObject;

        public Ziffernblatt(Graphics NgObject)
        {
            gObject = NgObject;

        }

        public void Draw(int PosX, int PosY)
        {
            RectSize.Width = PosX / 2;
            RectSize.Height = PosY / 2;

            RectPoint.X = PosX / 2 - RectSize.Width / 2;
            RectPoint.Y = PosY / 2 - RectSize.Height / 2;

            Myrect = new Rectangle(RectPoint, RectSize);
            MyCircle = new Rectangle(RectPoint, RectSize);

           gObject.DrawRectangle(Pens.Red, Myrect);
           gObject.DrawEllipse(Pens.Black, MyCircle);

           

        }

这是我的主要内容：

 public partial class Form1 : Form
    {
       
        Ziffernblatt[] Ziffern = new Ziffernblatt[1];
        Graphics gObject;

        public Form1()
        {
            
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
        }

        private void Form1_Paint(object sender, PaintEventArgs e)
        {
            gObject = e.Graphics;
            Ziffern[0] = new Ziffernblatt(gObject);
        }


        private void Form1_SizeChanged(object sender, EventArgs e)
        {
            Ziffern[0].Draw(this.ClientSize.Width, this.ClientSize.Height);
            Invalidate();
        }
    }

Answer 1

您收到此错误是因为您向您封装了 Graphics 对象 class。只需从 paint 事件中调用 draw 方法即可。绘图时的最佳实践是从 Form1 的 paint 方法执行的。考虑到 Graphics 对象将针对每个绘制事件更改。

您的代码可能如下所示：

public partial class Form1 : Form
{
    Ziffernblatt[] Ziffern = new Ziffernblatt[1];

    public Form1()
    {
        InitializeComponent();
        Ziffern[0] = new Ziffernblatt();
    }

    private void Form1_Load(object sender, EventArgs e)
    {            
    }

    private void Form1_Paint(object sender, PaintEventArgs e)
    {            
        Ziffern[0].Draw(e.Graphics, this.ClientSize.Width, this.ClientSize.Height);
    }

    private void Form1_SizeChanged(object sender, EventArgs e)
    {
        //Ziffern[0].Draw(this.ClientSize.Width, this.ClientSize.Height);
        Invalidate();
    }      
}


public class Ziffernblatt
{
    Size RectSize;

    Point RectPoint = new Point(5, 10);

    Rectangle Myrect;
    Rectangle MyCircle;

    Pen MyPen = new Pen(Color.Black, 1);
    Pen Invpen = new Pen(Color.White, 1);

    public Ziffernblatt() //Graphics NgObject)
    {
        //gObject = NgObject;
    }

    public void Draw(Graphics g, int PosX, int PosY)
    {
        RectSize.Width = PosX / 2;
        RectSize.Height = PosY / 2;

        RectPoint.X = PosX / 2 - RectSize.Width / 2;
        RectPoint.Y = PosY / 2 - RectSize.Height / 2;

        Myrect = new Rectangle(RectPoint, RectSize);
        MyCircle = new Rectangle(RectPoint, RectSize);

        g.DrawRectangle(Pens.Red, Myrect);
        g.DrawEllipse(Pens.Black, MyCircle);
    }
}

For additional information about the paint event see Control.Paint Event

用另一种方法画图class

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