用c#读取文件夹

Question

用c#读取文件夹，
并循环读取文件夹里的文件文本，怎么写？

Answer 1

// How much deep to scan. (of course you can also pass it to the method)
const int HowDeepToScan=4;public static void ProcessDir(string sourceDir, int recursionLvl) 
{
  if (recursionLvl<=HowDeepToScan)
  {
    // Process the list of files found in the directory.
    string [] fileEntries = Directory.GetFiles(sourceDir);
    foreach(string fileName in fileEntries)
    {
       // do something with fileName
       Console.WriteLine(fileName);
      string readText = File.ReadAllText(sourceDir + @"\" +  fileName);    }    // Recurse into subdirectories of this directory.
    string [] subdirEntries = Directory.GetDirectories(sourceDir);
    foreach(string subdir in subdirEntries)
       // Do not iterate through reparse points
       if ((File.GetAttributes(subdir) &
            FileAttributes.ReparsePoint) !=
                FileAttributes.ReparsePoint)            ProcessDir(subdir,recursionLvl+1);
  }
}

Answer 2

DirectoryInfo directoryInfo = new DirectoryInfo(filePath); 
string Content=string.Empty;
foreach (FileInfo fileInfo in directoryInfo.GetFiles("*.txt")) 
{ 
   Content+= File.ReadAllText(filePath+ @"\" +  fileInfo.Name);
                                 
} 

Answer 3

DirectoryInfo directoryInfo = new DirectoryInfo(filePath); 
string Content=string.Empty; 
foreach (FileInfo fileInfo in directoryInfo.GetFiles("*.txt")) 
{ 
  Content+= File.ReadAllText(fileInfo.FullName);                            
}