文件输入输出知识汇总

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;

namespace iio
{
    class Program
    {
        static void Main(string[] args)
        {
            // FileInfo f = new FileInfo("ir.txt");
            //// Console.WriteLine(f.Name);

            // //using (FileStream fs = f.Create())
            // //{
            // //}
            // using (StreamWriter sw = f.AppendText())
            // {
            //     sw.WriteLine("ii");
            // }
            // //FileStream fi = File.Create("");

            //获取一个FileStream对象
            using (FileStream fs = File.Open("one.dat", FileMode.Create))
            {
                //把字符串编码成字节数组
                string msg = "Hello";
                byte[] buffer = Encoding.Default.GetBytes(msg);

                //把byte[]写入文件
                fs.Write(buffer, 0, buffer.Length);

                //重置内部流的位置
                fs.Position = 0;

                byte[] rebyte = new byte[buffer.Length];

                for (int i = 0; i < buffer.Length; i++)
                {
                    rebyte[i] = (byte)fs.ReadByte();
                    Console.WriteLine(rebyte[i]);

                }
                Console.WriteLine(Encoding.Default.GetString(rebyte));
            }


            using (StreamWriter sw = File.CreateText("two.txt"))
            {
                sw.WriteLine("1");
                sw.WriteLine("2");
                sw.Write("3");
                sw.Write("3");
                sw.Write(sw.NewLine);
                sw.Write(9);
            }

            using (StreamReader sr = File.OpenText("two.txt"))
            {
                string input = null;
                while ((input = sr.ReadLine()) != null)
                {
                    Console.WriteLine(input);
                }
            }


            using (StringWriter sr = new StringWriter())
            {
                //sr.GetStringBuilder();

                sr.WriteLine("ioio");
                StringBuilder bu = sr.GetStringBuilder();
                bu.AppendLine("99");
                //    Console.WriteLine(bu);

                using (StringReader s = new StringReader(sr.ToString()))
                {
                    string input;
                    while ((input = s.ReadLine()) != null)
                    {
                        Console.WriteLine(input);
                    }
                }
            }


            FileInfo info = new FileInfo("binfile.txt");

            using (BinaryWriter bw = new BinaryWriter(info.OpenWrite()))
            {
                int num = 89090;
                bw.Write(num);
                bw.Write(9.8);
            }

            //从流中读取二进制数据
            using (BinaryReader br = new BinaryReader(info.OpenRead()))
            {
                Console.WriteLine(br.ReadInt32());
            }


            //确定指向要观察的目录路径
            FileSystemWatcher watcher = new FileSystemWatcher();
            watcher.Path = "folder";

            //设置需要"留意"的事情
            watcher.NotifyFilter = NotifyFilters.LastAccess
                | NotifyFilters.LastWrite
                | NotifyFilters.FileName
                | NotifyFilters.DirectoryName;


            //只观察文本文件
            watcher.Filter = "*.txt";
            watcher.Changed += new FileSystemEventHandler(OnChanged);

            //开始观察目录
            watcher.EnableRaisingEvents = true;



            Console.ReadLine();
        }

        static void OnChanged(object sender, FileSystemEventArgs e)
        {
            Console.WriteLine("Fil:{0} {1}", e.FullPath, e.ChangeType.ToString() == "Changed" ? "修改" : e.ChangeType.ToString());
        }
    }
}