.Net学习笔记----2015-06-25(文件流FileStream)

            //FileStream  操作字节的
            //StreamReader和StreamWriter 操作字符的
            FileStream fsRead = new FileStream(@"C:\Users\Administrator\Desktop\new.txt", FileMode.OpenOrCreate, FileAccess.Read);
            byte[] buffer = new byte[1024 * 1024 * 5];
            //3.8M 5M
            //返回本次实际读取到的有效字节数
            int r = fsRead.Read(buffer, 0, buffer.Length);
            //将字节数组中每一个元素按照指定的编码格式解码成字符串
            string s = Encoding.UTF8.GetString(buffer, 0, r);
            //关闭流
            fsRead.Close();
            //释放流所占用的资源
            fsRead.Dispose();
            Console.WriteLine(s);
            Console.ReadKey();

            //使用FileStream来写入数据
            //using (FileStream fsWrite = new FileStream(@"C:\Users\Administrator\Desktop\new.txt", FileMode.OpenOrCreate, FileAccess.Write))
            //{
            //    string str = "看我有木有把你覆盖掉";
            //    byte[] buffer = Encoding.UTF8.GetBytes(str);
            //    fsWrite.Write(buffer, 0, buffer.Length);
            //}
            //Console.WriteLine("OK");
            //Console.ReadKey();

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

namespace _08_使用文件流来实现多媒体文件的复制
{
    class Program
    {
        static void Main(string[] args)
        {
            string source = @"D:\Csharp教程\09-面向对象多态\2、File类的读写文件.avi";
            string target = @"C:\Users\Administrator\Desktop\File类的.avi";
            CopyFile(source, target);
            Console.WriteLine("复制成功");
            Console.ReadKey();
        }

        public static void CopyFile(string soucre, string target)
        {
            //1、创建一个负责读取文件的流
            using (FileStream fsRead = new FileStream(soucre, FileMode.Open, FileAccess.Read))
            {
                //2、创建一个负责写入的流
                using (FileStream fsWrite = new FileStream(target, FileMode.OpenOrCreate, FileAccess.Write))
                {
                    byte[] buffer = new byte[1024 * 1024 * 5];
                    //因为文件可能会比较大，所以在读取时候，通过循环去读取
                    while (true)
                    {
                        //返回本次读取实际读取到的字节数
                        int r = fsRead.Read(buffer, 0, buffer.Length);
                        //如果返回一个0，意味着什么也没读取到，读取完了
                        if (r == 0)
                        {
                            break;
                        }
                        fsWrite.Write(buffer, 0, r);
                    }

                }
            }
        }

    }
}