你的问题是

1.在方法前添加static

2.change Name方法

//String getString（）;
如果需要递归或重复方法，则必须检查并更改代码
这是正确的代码

using System;

namespace Paint;

class Program
{
    static void Main(string[] args)
    {
        Paintn();
    }
    static void Paintn()
    {
        string[] tiles = new string[256];
        var newkey = Console.Read();
        int paint = Convert.ToInt32(newkey);
        tiles[paint] = "Test";
        Console.WriteLine(tiles[paint]);
        Console.Beep();
        Console.ReadKey();
       // Paint();
    }
}

1.确保文件名为<something>.cs，如program.cs
1.编译器应该报告一些错误：

1. void static应为static void
2. Paint()方法也应该是static

using System;

namespace Paint
{

    class Program
    {
        static void Main(string[] args)
        {
            Paint();
        }
        static void Paint()
        {
            string[] tiles = new string[256];
            var newkey = Console.Read();
            int paint = Convert.ToInt32(newkey);
            tiles[paint] = "Test";
            Console.WriteLine(tiles[paint]);
            Console.Beep();
            Console.ReadKey();
            Paint();
        }
    }
}