如何在 C# 控制台中打印圆圈

Question

using System;

namespace CirclePrint
{
    enum EShape
    {
        Rectangle,
        IsoscelesRightTriangle,
        IsoscelesTriangle,
        Circle
    }

    internal class Program
    {

        static void Main(string[] args)
        {
            uint width = 21;
            uint height = 21;

            char[,] canvas = Draw(width, height, EShape.Circle);
        }

        public static char[,] Draw(uint width, uint height, EShape shape)
        {
            if (width == 0 || height == 0)
            {
                return new char[0, 0];
            }
            uint col = height + 4;
            uint row = width + 4;

            char[,] canvas = new char[col, row];

            uint r = row / 2;

            int centerX = (int)row / 2;
            int centerY = (int)col / 2;


            switch (shape)
            {
                case EShape.Circle:
                    if (width != height)
                    {
                        return new char[0, 0];
                    }
                    else if (width / 2 == 0)
                    {
                        return new char[0, 0];
                    }


                    for (int y = 0; y < col; y++)
                    {
                        for (int x = 0; x < row; x++)
                        {
                            // upper side, Bottom side
                            if (y == 0 || y == col - 1)
                            {
                                canvas[y, x] = '-';
                                Console.Write(canvas[y, x]);
                            }


                            // left, right side
                            if (y != 0 && y != col - 1)
                            {
                                if (x == 0 || x == row - 1)
                                {
                                    canvas[y, x] = '|';
                                    Console.Write(canvas[y, x]);
                                }
                                else if (y == 1 || y == col - 2) 
                                {
                                    canvas[y, x] = ' ';
                                    Console.Write(canvas[y, x]);
                                }
                                else if (x == 1 || x == row - 2) 
                                {
                                    canvas[y, x] = ' ';
                                    Console.Write(canvas[y, x]);
                                }
                                else if (y >= 2 || y <= col - 2) // circle print
                                {
                                    int dx = x - centerX;
                                    int dy = y - centerY;

                                    if (dx * dx + dy * dy <= r * r)
                                    {
                                        canvas[y, x] = '*';
                                        Console.Write(canvas[y, x]);
                                    }
                                    else
                                    {
                                        canvas[y, x] = ' ';
                                        Console.Write(canvas[y, x]);
                                    }

                                }
                            }
                        }
                        Console.WriteLine();
                    }

                    break;
            }

            return canvas;
        }
    }
}

我的能力解决不了，所以问了个问题。此代码根据输入的宽度和高度值在可变形矩形框内输出一个圆。

我想要的是像这里的截图一样打印一个圆圈。如图所示，我写的代码输出了一个愚蠢的八角形......

我无法解决的部分是我写'circle print'作为评论的部分。

我认为找到'centerX,Y'的值可以解决这个问题，但我不确定这是否属实。