c#第九课 linq stream（2）

流用于对IO处理

在System.IO名称空间中有以下类

BinaryReader/Writer

TextReader/Writer

Stream

其中类Stream为抽象类。由此有三个派生类：

MemoryStream：对内存进行读取与写入

BufferedStream：对缓冲器进行读取/写入

FileStream：对文件执行读取与写入

TextReader/Writer为抽象类。由此派生类：

StreamReader/StreamWirter

StringReader/StreamWriter

需要引入命名空间:

using System.IO

 

文件流的使用

string s=Console.ReadLine(); 

FileStream fileStream=new FileStream(s,FileMode.OpenOrCreate); 

BinaryWriter binStream=new BinaryWriter (fileStream); 

for(int i=1;i<=10;i++) 

{ 

binStream.Write((int)i); 

} 

binStream.Close(); 

fileStream.Close(); 

FileStream f=new FileStream(s,FileMode.Open,FileAccess.Read,FileShare.ReadWrite); 

BinaryReader buf=new BinaryReader(f); 

for(int i=1;i<10;i++) 

{ 


Console.WriteLine("输出{0}",buf.ReadByte ()); //在vs2012中这样不能读出东西来

Console.WriteLine("输出{0}",Bur.ReadInt32());才行，因为int是32位的

}

 2 递归显示目录

 1 using System;
 2 using System.Collections.Generic;
 3 using System.IO;
 4 using System.Text;
 5 
 6 namespace StreamTester
 7 {
 8     class Tester
 9     {
10         static int dirCounter = 1;
11         static int indentLevel = -1;
12 
13         public static void Main()
14         {
15             Tester t = new Tester();
16 
17             // 选择根目录
18             string theDirectory =
19             Environment.GetEnvironmentVariable("SystemRoot");
20             // 如果是在unix linux 等其他系统下，要加下面一句话
21             //string theDirectory = "/tmp";
22 
23             //下面调用方法来浏览该目录，显示数据及子目录
24 
25             DirectoryInfo dir = new DirectoryInfo(theDirectory);
26 
27             t.ExploreDirectory(dir);
28 
29             Console.WriteLine(
30                 "\n\n{0} directories found.\n",
31                 dirCounter);
32         }
33 
34         // 只要找到一个目录就递归的递归的调用自己
35 
36         private void ExploreDirectory(DirectoryInfo dir)
37         {
38             indentLevel++; // 目录层次++
39 
40             for (int i = 0; i < indentLevel; i++)
41                 Console.Write(" "); 
42 
43             Console.WriteLine("[{0}] {1} [{2}]\n",
44                 indentLevel, dir.Name, dir.LastAccessTime);
45 
46             // 得到dir下的所有子目录存入directories[]中
47             DirectoryInfo[] directories = dir.GetDirectories();
48             foreach (DirectoryInfo newDir in directories)
49             {
50                 dirCounter++;
51                 ExploreDirectory(newDir); // 递归调用
52             }
53             indentLevel--; //目录层次--
54         }
55     }
56 }

 结果显示为

 

 

 

读网页内容

1 public class Client
 2     {
 3         static public void Main(string[] Args)
 4         {
 5             // http request请求
 6             HttpWebRequest webRequest =
 7                 (HttpWebRequest)WebRequest.Create
 8                     ("http://www.baidu.com/");
 9 
10             // httq response
11             HttpWebResponse webResponse =
12                 (HttpWebResponse)webRequest.GetResponse();
13 
14             // 对response的返回内容读入
15             StreamReader streamReader = new StreamReader(
16                 webResponse.GetResponseStream(), Encoding.ASCII);
17 
18             try
19             {
20                 string outputString;
21                 outputString = streamReader.ReadToEnd();
22                 Console.WriteLine(outputString);
23             }
24             catch
25             {
26                 Console.WriteLine("Exception reading from web page");
27             }
28             streamReader.Close();
29             Console.ReadKey();
30         }
31     }

 输出结果为