C#中File和FileStream的简单介绍和用法

 string path = @"C:\Users\Administrator\Desktop\1.txt";
 File.Open(path, FileMode.OpenOrCreate);

 List<string> users = new List<string>();
   users.Add("张三|1000");
   users.Add("李四|10000");
   users.Add("王五|5000");
   users.Add("赵六|6000");
    File.AppendAllLines(path, users, Encoding.Default);

byte[] buttf = File.ReadAllBytes(path);
string str = Encoding.Default.GetString(buttf, 0, buttf.Length);

 string[] filestr = File.ReadAllLines(path, Encoding.Default);
 for (int i = 0; i < filestr.Length; i++)
  {
  string[] str = filestr[i].Split('|');
  filestr[i] = str[0] + "|" + (Convert.ToDouble(str[1]) * 2).ToString();
  }
  File.AppendAllLines(path, filestr, Encoding.Default);

 byte[] bytsize = new byte[1024 * 1024 * 5];
   using (FileStream stream = new FileStream(path, FileMode.OpenOrCreate,FileAccess.ReadWrite))
   {
    while (true)
    {
     int r = stream.Read(bytsize, 0, bytsize.Length);
     //如果读取到的字节数为0，说明已到达文件结尾，则退出while循
     if (r == 0)
     {
      break;
     }
 
     string str = Encoding.Default.GetString(bytsize, 0, r);
     Console.WriteLine(str);
    }
   }

 string str = "今天天气好晴朗，处处好风光";
   byte[] buttf = Encoding.Default.GetBytes(str);
   //文件流的写入
   using (FileStream fscreat = new FileStream(path, FileMode.Append, FileAccess.Write))
   {
 
    fscreat.Write(buttf, 0, buttf.Length);
   }

 byte[] bytsize = new byte[1024 * 1024 * 5];  
string videoPath = @"C:\Users\Administrator\Desktop\1、练习1-3.avi";
   string videoNewPath = @"C:\Users\Administrator\Desktop\1.avi";
   //创建读取流
   using (FileStream fsread=new FileStream(videoPath,FileMode.Open,FileAccess.Read))
   {
    //创建写入流
    using (FileStream fswrite=new FileStream(videoNewPath,FileMode.OpenOrCreate,FileAccess.Write))
    {
      while (true)
     {
     //返回实际读取到的字节
     int r = fsread.Read(bytsize, 0, bytsize.Length);
     //当字节位0的时候 证明已经读取结束
     if(r==0){
      break;
     }
     fswrite.Write(bytsize,0,r);
 
    }
    }
    
   }