using System;
using System.IO;
class file1 {
  public static void Main()
  {
    string PATH = null;
    Console.WriteLine("file path: ");
    //这里输入文本所在目录 例如 d:\text.txt
    PATH = Console.ReadLine();
    StreamWriter sw = new StreamWriter(PATH);
    string str = null;
    while(true){
      str = Console.ReadLine();
      if (str == "end") {
        break;
      }
      sw.WriteLine(str);
    }
    sw.Close(); 
    Console.ReadKey();
  }
}

using System;
using System.IO;
class file1 {
  public static void Main() {
    string PATH = null;
    Console.WriteLine("file path: ");
    //这里输入文本所在目录 例如 d:\text.txt
    PATH = Console.ReadLine();
    StreamReader r = File.OpenText(PATH);
    while(!r.EndOfStream){
      Console.WriteLine(r.ReadLine());
    }
    Console.ReadKey();
  }
}