C# File和fileinfo类

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.IO;

namespace file_Operations
{
    class Program
    {
        static void Main(string[] args)
        {
            FileStream fs = null;
            StreamWriter writer = null;
            //文件路径
            string path = "D:\\test.txt";
            //判断路径下文件是否存在
            if (!File.Exists(path))
            {
                fs = File.Create(path);
                Console.WriteLine("新建一个文件:{0}",path);
            }
            else
            {
                fs = File.Open(path,FileMode.Open);
                Console.WriteLine("文件已存在直接打开");
            }
            //初始化对象
            writer = new StreamWriter(fs);
            writer.Write("test文本");
            Console.WriteLine("向文本中写入数据");
            //关闭缓存
            writer.Flush();
            writer.Close();
            fs.Close();
            Console.WriteLine("关闭数据流");
        }
    }
}