如何將文本附加到C＃中所有現有的.txt文檔？

Question

所以我有這樣的代碼：

class Program 
    { 

     static void Main(string[] args) 
     { 
      // Set a variable to the My Documents path. 
      string mydocpath = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments); 

      var dir = new DirectoryInfo(mydocpath + @"\sample\"); 
      string msg = "Created by: Johny"; 

      foreach (var file in dir.EnumerateFiles("*.txt")) 
      { 
       file.AppendText(msg); //getting error here 
      } 
     } 
    } 

而且我想頁腳添加到樣本文件夾中所有的文本文件，但由於AppendText通過不接受一個字符串參數，我得到一個錯誤。我只是想知道我該怎麼做？

Answer 1

你想用從AppendText通過我認爲的StreamWriter：

 static void Main(string[] args) 
     { 
      // Set a variable to the My Documents path. 
      string mydocpath = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments); 

      var dir = new DirectoryInfo(mydocpath + @"\sample\"); 
      string msg = "Created by: Johny"; 

      foreach (var file in dir.EnumerateFiles("*.txt")) 
      { 
       var streamWriter = file.AppendText(); 
       streamWriter.Write(msg); 
       streamWriter.Close(); 
      } 
     } 

Answer 2

FileInfo.AppendText()創建一個StreamWriter，它不會附加文本本身。要做到這一點：

using (var sw = file.AppendText()) { 
    sw.Write(msg); 
} 

Answer 3

AppendText對於StreamWriter擴展方法，請參閱documentation

所以，你應該請寫下這些代碼：

foreach (var file in dir.EnumerateFiles("*.txt")) 
{ 
    using (StreamWriter sw = File.AppendText(file.FullName)) 
    { 
     sw.WriteLine(msg); 
    } 
}