C#.NET向現有檔案添加文本+建立一個新文字檔並寫入一個字串

向現有檔案添加文本:

using System;using System.IO;class Test{public static void Main(){// Create an instance of StreamWriter to write text to a file.// The using statement also closes the StreamWriter.using (StreamWriter sw = new StreamWriter("TestFile.txt")){// Add some text to the file.sw.Write("This is the ");sw.WriteLine("header for the file.");sw.WriteLine("-------------------");// Arbitrary objects can also be written to the file.sw.Write("The date is: ");sw.WriteLine(DateTime.Now);}}}

建立一個新文字檔並寫入一個字串:

using System;using System.IO;public class TextToFile{private const string FILE_NAME = "MyFile.txt";public static void Main(String[] args){if (File.Exists(FILE_NAME)) // 確認檔案是否存在.{Console.WriteLine("{0} already exists.", FILE_NAME);return;}using (StreamWriter sw = File.CreateText(FILE_NAME)){sw.WriteLine ("This is my file.");sw.WriteLine ("I can write ints {0} or floats {1}, and so on.",1, 4.2);sw.Close();}}}