FileStream -- 复制文件

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

 //添加命名空间
 using System.IO;

 namespace 文件流
 {
     class Program
     {
         static void Main(string[] args)
         {
             string source = @"C:\Users\Administrator\Desktop\增加.gif";

             string target = @"C:\Users\Administrator\Desktop\new.gif";

             Command.CopyFile(source, target);

             Console.WriteLine("复制成功！");

             Console.ReadKey();
         }
     }

     //操作类
     public class Command
     {
         public static void CopyFile(string source, string target)
         {
             //创建读取流
             using(FileStream fsRead = new FileStream(source, FileMode.Open, FileAccess.Read))
             {
                 //创建写入流
                 using(FileStream fsWrite = new FileStream(target, FileMode.OpenOrCreate, FileAccess.Write))
                 {
                     //字节数组，存放取出的字节数
                     byte[] buffer = new byte[ *  * ];

                     //循环，当i！=0的时候循环
                     while (true)
                     {
                         //当前是假存到字节数组中的字节数
                         int i = fsRead.Read(buffer, , buffer.Length);

                         //如果i==0，break；
                         if (i == )
                         {
                             break;
                         }

                         //写入数据
                         fsWrite.Write(buffer, , i);
                     }
                 }
             }
         }
     }
 }