Summary of operation methods of C file directory

Need using System. IO;

1) Relative path to absolute path

string fullfolder = HttpContext.Current.Server.MapPath(folder);

2) File movement (renamed)

File.Move(Server.MapPath("/a.txt"), Server.MapPath("/b.txt"));

3) File copying

File.Copy(Server.MapPath("/a.txt"), Server.MapPath("/b.txt"), true);

4) Does the file exist

File.Exists(filefullname)

5) Does the directory exist

Directory.Exists(fullfolder))

6) Create a directory

Directory.CreateDirectory(fullfolder);

7) Directory Move

Directory.Move

8) Reading a text file

StreamReader srd = File.OpenText(fullfilename);
srd.ReadToEnd();
srd.Close();
srd.Dispose();

9) Write files

StreamWriter swr = File.CreateText(Server.MapPath("test.txt"));
swr.Write("message");
swr.Close();
swr.Dispose();

10) Delete files

//Delete files on hard disk
if (File.Exists(filefullname))
{
File.Delete(filefullname);
}

11) Directory traversal

public void ListFiles(string pathname)
{
//All directories and files
string[] subDirs = Directory.GetDirectories(pathname);
string[] subFiles = Directory.GetFiles(pathname);
foreach (string subDir in subDirs)
{
ListFiles(subDir);
}
//All files
foreach (string subFile in subFiles)
{
string filename = Path.GetFileName(subFile);
}
}

12) File modification time

FileInfo fi = new FileInfo(@"c:\test.txt");
DateTime writetime = fi.LastWriteTime;

13) Extract the file name from the file name with the path

System. IO. Path. GetFileName (fullPath); //Filename