C# 文件操做總結

時間 2019-12-12

標籤 c# 文件總結欄目 C# 简体版

原文原文鏈接

1、需求分析web

　　1.將信息記錄到本地記事本中。服務器

　　2.將記錄的信息讀取出來。網絡

　　3.計算出某個文件夾下全部後綴名爲txt的數量和dll的數量。url

　　4.從網絡上下載文件。spa

2、二話不說上代碼3d

 1 using System;
 2 using System.IO;
 3 using System.Text;
 4 
 5 namespace FileOperation
 6 {
 7     class Program
 8     {
 9         static void Main(string[] args)
10         {
11             SaveLoginInfo();
12             ReadLoginInfo();
13             Ergodic();
14         }
15 
16 
17         /// <summary>
18         /// 本地文件中保存登陸信息
19         /// </summary>
20         static void SaveLoginInfo()
21         {
22             #region 在本地保存登陸信息
23             //判斷文件是否存在
24             string loginDicPath = "E:\\Login";
25             if (!Directory.Exists(loginDicPath))
26             {
27                 Directory.CreateDirectory(loginDicPath);
28             }
29             string loginFilePath = loginDicPath + "\\login.txt";
30             //能夠指定盤符，也能夠指定任意文件名，還能夠爲word等文件
31             FileStream fs = new FileStream(loginFilePath, FileMode.OpenOrCreate, FileAccess.ReadWrite);
32             //建立寫入流
33             StreamWriter sw = new StreamWriter(fs);
34             string testContent = "用戶已登陸";
35             sw.WriteLine(testContent);
36             sw.Close();
37             #endregion
38         }
39 
40         /// <summary>
41         /// 讀取登陸信息
42         /// </summary>
43         static void ReadLoginInfo()
44         {
45             string loginFilePath = "E:\\Login\\login.txt";
46             if (File.Exists(loginFilePath))
47             {
48                 StreamReader st = new StreamReader(loginFilePath, Encoding.UTF8);
49                 string content = st.ReadToEnd();
50                 st.Close();
51                 Console.WriteLine(content);
52             }
53         }
54 
55         /// <summary>
56         /// 遍歷文件夾，計算文件夾中txt的數量和dll的數量
57         /// </summary>
58         static void Ergodic()
59         {
60             string loginDicPath = "E:\\testDic";
61             DirectoryInfo root = new DirectoryInfo(loginDicPath);
62             DirectoryInfo[] dics = root.GetDirectories();
63             int txtNum = 0;
64             int dllNum = 0;
65             foreach (DirectoryInfo info in dics)
66             {
67                 string path = info.FullName;
68                 //獲取該文件夾下的全部文件
69                 DirectoryInfo root_Children = new DirectoryInfo(path);
70                 FileInfo[] filesChildren = root_Children.GetFiles();
71                 //獲取完整路徑名
72                 foreach (FileInfo fileInfo in filesChildren)
73                 {
74                     if (fileInfo.Extension == ".txt")
75                     {
76                         txtNum += 1;
77                     }
78                     else if (fileInfo.Extension == ".dll")
79                     {
80                         dllNum += 1;
81                     }
82                     else
83                     {
84                     }
85                 }
86             }
87             Console.WriteLine("txt的數量爲{0},dll的數量爲{1}", txtNum, dllNum);
88         }
89     }
90 }

注：對於需求3的目錄結構以下code

需求4的代碼（下載網絡文件到本地）對象

 1 using System;
 2 using System.Linq;
 3 using System.Net;
 4 
 5 namespace FileOperation
 6 {
 7     class Program
 8     {
 9         static void Main(string[] args)
10         {
11             DownloadWebFile();
12         }
13 
14 
15         /// <summary>
16         /// 下載網絡文件
17         /// </summary>
18         static void DownloadWebFile()
19         {
20             //網絡文件地址
21             string webFileUrl = "http://127.0.0.1:8088//error-file.txt";
22             //下載地址
23             string myDictionary = AppDomain.CurrentDomain.BaseDirectory;
24             //獲取文件名稱
25             string fileName = GetFileName(webFileUrl);
26             if (!HttpFileExist(webFileUrl))
27             {
28                 Console.WriteLine("服務器上沒有該文件");
29                 return;
30             }
31             else
32             {
33                 WebClient client = new WebClient();
34                 client.DownloadFile(webFileUrl, myDictionary + "/" + fileName);
35             }
36 
37         }
38 
39         /// <summary>
40         /// 判斷網絡文件是否存在
41         /// </summary>
42         /// <param name="fileUrl"></param>
43         /// <returns></returns>
44         static bool HttpFileExist(string fileUrl)
45         {
46             try
47             {
48                 //建立根據網絡地址的請求對象
49                 HttpWebRequest httpWebRequest = (HttpWebRequest)WebRequest.CreateDefault(new Uri(fileUrl));
50                 httpWebRequest.Method = "HEAD";
51                 httpWebRequest.Timeout = 1000;
52                 //返回響應狀態是不是成功比較的布爾值
53                 using (HttpWebResponse response = (HttpWebResponse)httpWebRequest.GetResponse())
54                 {
55                     return response.StatusCode == HttpStatusCode.OK;
56                 }
57             }
58             catch (Exception ex)
59             {
60                 return false;
61             }
62         }
63 
64         /// <summary>
65         /// 獲取文件名稱
66         /// </summary>
67         /// <param name="url"></param>
68         /// <returns></returns>
69         private static string GetFileName(string url)
70         {
71             string fileName = "";
72             string[] str = url.Split('/');
73             fileName = str.Last();
74             return fileName;
75         }
76     }
77 }