大文件流操作及编码

（一）大文件流操作
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;

namespace 文件流
{
    class Program
    {
        static void Main(string[] args)
        {



            //string str = @"C:\Documents and Settings\steve\桌面\net1017\net基础加强\案例素材\1.rmvb";
            //byte[] byts = File.ReadAllBytes(str);
            //Console.ReadKey();

            //将1.rmvb 拷贝到 d:\1.rmvb
            string source = @"C:\Documents and Settings\steve\桌面\net1017\net基础加强\案例素材\1.rmvb";
            string target = @"d:\1.rmvb";
            CopyFile(source, target);
            Console.WriteLine("ok");
            Console.ReadKey();

        }
        static void CopyFile(string sourc, string target)
        {
            #region MyRegion
            // // 创建一个文件流
            // FileStream fsRead = new FileStream(sourc, FileMode.Open);



            // //
            // //
            //// fsRead.Flush();//将缓冲区的数据写入到流中。
            // //文件流使用完成以后必须关闭
            // fsRead.Close();
            // //用来释放一些非托管资源的。
            // fsRead.Dispose();

            //using (FileStream fsRead = new FileStream(sourc, FileMode.Open))
            //{
            //    //在using的小括号中包含的对象，当出了using的作用域范围以后
            //    //会自动调用该对象的Dispose()方法。
            //    //对于文件流调用Dispose()方法的时候会自动调用close()方法。
            //    //fsRead.Dispose();   
            //}
            //...

            //using (Person p = new Person())
            //{

            //}
            //Console.ReadKey();
            #endregion

            //创建一个读取文件的文件流
            FileStream fsRead = new FileStream(sourc, FileMode.Open);

            // 创建一个写入文件流
            FileStream fsWrite = new FileStream(target, FileMode.Create);
            using (fsRead)
            {
                using (fsWrite)
                {
                    long sum = fsRead.Length;
                    double readByte = 0;
                    //每次从文件中读取5MB,到内存中。
                    byte[] byts = new byte[1024 * 1024 * 5];
                    while (true)
                    {


                        //这个b就表示本次实际读取到的字节数。
                        //参数1：要将数据存放到的数组中。
                        //参数2：这个数组从第几个元素开始存储
                        //参数3：本次读取最多能读取多少个字节。
                        int b = fsRead.Read(byts, 0, byts.Length);
                        readByte += b;
                        // 如果本次没有读取到任何字节，则认为已经读取完毕，跳出循环
                        if (b <= 0)
                        {
                            break;
                        }
                        //fsWrite.Position

                        //参数1：要将那个数组中的数据写入文件
                        //参数2：从这个数组的第几个元素开始写
                        //参数3：本次要写的字节数（一般为上次实际读取的字节数）
                        fsWrite.Write(byts, 0, b);
                        //Console.Write(".");
                        Console.WriteLine((readByte / sum) * 100 + "%");

                    }


                }
            }






        }
    }

    public class Person : IDisposable
    {
        public string Name
        {
            get;
            set;
        }
        public int Age
        {
            get;
            set;
        }
        public string Email
        {
            get;
            set;
        }


        #region IDisposable 成员

        public void Dispose()
        {
            Console.WriteLine("......................");
        }

        #endregion
    }
}
（二）文件编码
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.IO;

namespace _02_文件操作
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            //选择文件
            OpenFileDialog ofd = new OpenFileDialog();

            ofd.Filter = "文本文件|*.txt|所有文件|*.*";
            if (ofd.ShowDialog() == System.Windows.Forms.DialogResult.OK)
            {
                textBox1.Text = ofd.FileName;
            }
        }

        private void button2_Click(object sender, EventArgs e)
        {
            //文件流的方式 读取文件

            using (FileStream fs = new FileStream(textBox1.Text, FileMode.Open))
            {
                byte[] buffer = new byte[1024*1024*5];
                //把流中的内容读取到字节数组中
                int length = fs.Read(buffer, 0, buffer.Length);

                //字节数组转换成字符串
               textBox2.Text =  System.Text.Encoding.GetEncoding("gbk").GetString(buffer);
            }

           
        }

        //选择要保存文件的路径
        private void button4_Click(object sender, EventArgs e)
        {
            SaveFileDialog sfd = new SaveFileDialog();

            sfd.Filter = "文本文件|*.txt";

            if (sfd.ShowDialog() == System.Windows.Forms.DialogResult.OK)
            {
                textBox3.Text = sfd.FileName;
            }
        }

        private void button3_Click(object sender, EventArgs e)
        {
            //写入文件
            using(FileStream fs = new FileStream(textBox3.Text,FileMode.Create))
            {
                //字符串转换成字节数组
                byte[] buffer = System.Text.Encoding.GetEncoding("gbk").GetBytes(textBox4.Text);
                //把字节数组通过文件流写入文件
                fs.Write(buffer, 0, buffer.Length);
            }
        }
    }
}