C#基础 字符串读取/写入文本文件 代码示例

写入文本文件：

class Program  2  {  3 static void Main(String[] args)  4  {  5 //写入string数组，每个string一行  6 string[] lines = { "first line", "second line ", "third line", "forth line" };  7 System.IO.File.WriteAllLines(@"D:\IOTest\IOTest1.txt", lines);  8 //写入一个字符串  9 string text = "ahhhhhhhhhhhhhhhhhhhhhhhhhhh"; 10 System.IO.File.WriteAllText(@"D:\IOTest\IOTest2.txt", text); 11 //StreamWriter类，以流的方式写入 12 System.IO.StreamWriter file = new System.IO.StreamWriter(@"D:\IOTest\IOTest3.txt", true); 13 foreach (var line in lines) 14  { 15 if (!line.Contains("second")) 16  { 17  file.Write(line); 18  file.WriteLine(line); 19  } 20  } 21  file.Flush(); 22  file.Close(); 23  } 24 }

 

读取文本文件：

class Program  2  {  3 static void Main(String[] args)  4  {  5 //读取为一个字符串  6 string text = System.IO.File.ReadAllText(@"D:\iOTEST\IOTEST2.TXT");  7 //读取为字符串数组，每行一个字符串  8 string[] lines = System.IO.File.ReadAllLines(@"D:\IOTEST\IOTEST1.TXT");  9 //StreamReader类，以流的方式读取 10 System.IO.StreamReader sr = new System.IO.StreamReader(@"D:\iOTEST\IOTEST3.TXT"); 11 string str; 12 while ((str = sr.ReadLine()) != null) 13  { 14  Console.WriteLine(str); 15  } 16  sr.Close(); 17  } 18 }