FileStream类读取文件，写入文件

FileStream类读取文件，写入文件

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

namespace _03FileStream类
{
    class Program
    {
        static void Main(string[] args)
        {
            //FileStream  读取文件;
            string fPathr = @"E:\dotNet\Study\2.txt";
            FileStream fsRead = new FileStream(fPathr, FileMode.OpenOrCreate, FileAccess.Read, FileShare.Read);
            byte[] buffer = new byte[1024 * 1024 * 5];
            int r = fsRead.Read(buffer, 0, buffer.Length);
            string s = Encoding.Default.GetString(buffer, 0, r);
            fsRead.Close();
            fsRead.Dispose();

            Console.WriteLine(s);
            Console.ReadKey();


            //FileStream 写入文件;
            string fPathw = @"E:\dotNet\Study\1.txt";
            using (FileStream fsWrite = new FileStream(fPathw, FileMode.Append, FileAccess.Write, FileShare.Read))
            {
                string str = "看看我会不会把你给覆盖掉~~~！！！";
                Byte[] buffer1 = Encoding.Default.GetBytes(str);
                fsWrite.Write(buffer1, 0, buffer1.Length);              
            }
            Console.WriteLine("Add Success!!");
            Console.ReadKey();

        }
    }
}