using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.IO;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

using System.Windows.Forms;

//*************************************************************************************

//**********************黑马程序员/Asp.Net/技术群：118041544 **************************

//*************************************************************************************

namespace 大文件拷贝

{

    public partial class Form1 : Form

    {

        public Form1()

        {

            InitializeComponent();

        }

        private string _fileName;

        private void button1_Click(object sender, EventArgs e)

        {

            OpenFileDialog ofd = new OpenFileDialog();

            if (ofd.ShowDialog() == DialogResult.OK)

            {

                this.textBox1.Text = ofd.FileName;

                _fileName = ofd.SafeFileName;

            }

        }

        private void button2_Click(object sender, EventArgs e)

        {

            FolderBrowserDialog fbd = new FolderBrowserDialog();

            if (fbd.ShowDialog() == DialogResult.OK)

            {

                this.textBox2.Text = fbd.SelectedPath;

            }

        }

        private void button3_Click(object sender, EventArgs e)

        {

            this.progressBar1.Value = ;

            this.label1.Text = "0%";

            if (!File.Exists(this.textBox1.Text))

            {

                MessageBox.Show("找不到目标文件！");

                return;

            }

            if (!Directory.Exists(this.textBox2.Text))

            {

                MessageBox.Show("请选择有效的保存路径！");

                return;

            }

            string fileRead = this.textBox1.Text;

            string fileSave = this.textBox2.Text + "/" + _fileName;

            System.Threading.ThreadPool.QueueUserWorkItem((o) =>

            {

                using (IDisposable file = new FileStream(fileRead, FileMode.Open, FileAccess.Read),

                fileWrite = new FileStream(fileSave, FileMode.Create, FileAccess.Write))

                {

                    int count = ;

                    long fileLength = ((FileStream)file).Length; //目标文件大小

                    double n = ( * 1.0 / fileLength);  //每次进度条累加

                    double m = ;                         //累加统计

                    int spam = ;                         //时间间隔

                    double speed = ;                     //拷贝速度

                    do

                    {

                        DateTime time = DateTime.Now;

                        count = ((FileStream)file).ReadByte();

                        ((FileStream)fileWrite).WriteByte((byte)count);//按一个字节一个字节写入

                        //计算速度 单位k/s

                        speed = (1.0 *  / ) / spam;

                        //进度条

                        m = m + n;

                        //控件显示

                        ShowProbar(o, m, speed);

                        //保存时间间隔，单位毫秒

                        spam = (DateTime.Now - time).Milliseconds >  ? (DateTime.Now - time).Milliseconds : spam;//必须大于0

                    } while (count != -);

                }

                if (this.progressBar1.Value == )

                {

                    System.Threading.Thread.Sleep(); //延迟1秒弹出

                    MessageBox.Show("拷贝成功！");

                }

            });

        }

        private void button4_Click(object sender, EventArgs e)

        {

            this.progressBar1.Value = ;

            this.label1.Text = "0%";

            if (!File.Exists(this.textBox1.Text))

            {

                MessageBox.Show("找不到目标文件！");

                return;

            }

            if (!Directory.Exists(this.textBox2.Text))

            {

                MessageBox.Show("请选择有效的保存路径！");

                return;

            }

            string fileRead = this.textBox1.Text;

            string fileSave = Path.Combine(this.textBox2.Text, _fileName);

            System.Threading.ThreadPool.QueueUserWorkItem((o) =>

            {

                using (IDisposable file = new FileStream(fileRead, FileMode.Open, FileAccess.Read),

                    fileWrite = new FileStream(fileSave, FileMode.Create, FileAccess.Write))

                {

                    int count = ;

                    long fileLength =((FileStream)file).Length; //目标文件大小

                    //根据目标文件大小创建byte数组长度

                    byte[] data = new byte[fileLength >  *  *  ?  *  *  : fileLength]; //30M 1024 * 1024 * 30

                    int step = (int)Math.Ceiling(fileLength * 1.0 / data.Length); //分流段数

                    double n = ( * 1.0 / step);  //每次进度条累加

                    double m = ;                   //累加统计

                    int spam = ;                   //时间间隔

                    double speed = ;               //拷贝速度

                    do

                    {

                        DateTime time = DateTime.Now;

                        //文件流操作

                        count = ((FileStream)file).Read(data, , data.Length);

                        ((FileStream)fileWrite).Write(data, , count);

                        //保存时间间隔，单位毫秒

                        spam = (DateTime.Now - time).Milliseconds >  ? (DateTime.Now - time).Milliseconds : spam;//必须大于0

                        //计算速度 单位k/s

                        if (count == data.Length)

                        {

                            speed = (count * 1.0 /  / spam) * ;

                        }

                        //进度条

                        m = m + n;

                        //控件显示

                        ShowProbar(o, m, speed);

                    } while (count > );

                }

                if (this.progressBar1.Value == )

                {

                    System.Threading.Thread.Sleep(); //延迟1秒弹出

                    MessageBox.Show("拷贝成功！");

                }

            });

        }

        private void ShowProbar(object o, double m, double speed)

        {

            try

            {

                int barValue = (int)Math.Floor(m) >=  ?  : (int)Math.Floor(m);

                this.Invoke((MethodInvoker)(() =>

                {

                    this.progressBar1.Value = barValue;

                    this.label1.Text = barValue.ToString() + "%";

                    this.label2.Text = speed >=  ? (speed / ).ToString("0.0m/s") : (speed >=  ? speed.ToString("0k/s") : (speed * ).ToString("0b/s"));

                }));

            }

            catch (Exception e)

            {

                throw new Exception(e.Message);

            }

        }

    }

}