c#根据文件大小显示文件复制进度条实例

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.IO;
using System.Threading;  
 namespace CopyProgress015
{
public partial class Form1 : Form
{
    public Form1()
    {
 InitializeComponent();
    }
    private Thread thdCopyFile; //创建一个线程
    private string str = "";  //用来记录源文件的名字
    FileStream FormerOpenStream;  //实例化源文件FileStream类
    FileStream ToFileOpenStream;  //实例化目标文件FileStream类 
 
    #region //复制文件 函数
    /// <summary>
    /// 复制文件
    /// </summary>
    /// <param name="FormerFile">源文件路径</param>
    /// <param name="ToFile">目的文件路径</param>
    /// <param name="TranSize">传输大小</param>
    /// <param name="progressBar1">ProgressBar控件</param>
    public void CopyFile(string FormerFile, string ToFile, int TranSize, ProgressBar progressBar1)
    {
 progressBar1.Value = 0;//设置进度条的当前位置为0
 progressBar1.Minimum = 0; //设置进度条的最小值为0 
  try
 {
     FormerOpenStream = new FileStream(FormerFile, FileMode.Open, FileAccess.Read);//以只读方式打开源文件
 }
 catch (IOException ex)
 {
     MessageBox.Show(ex.Message);
     return;
 } 
  try
 {
     FileStream fileToCreate = new FileStream(ToFile, FileMode.Create); //创建目的文件，如果已存在将被覆盖
     fileToCreate.Close();//关闭所有fileToCreate的资源
     fileToCreate.Dispose();//释放所有fileToCreate的资源
 }
 catch(IOException ex)
 {
     MessageBox.Show(ex.Message);
     return;
 } 
 
       ToFileOpenStream = new FileStream(ToFile, FileMode.Append, FileAccess.Write);//以写方式打开目的文件 
 
       int max = Convert.ToInt32(Math.Ceiling((Double)FormerOpenStream.Length / (Double)TranSize));//根据一次传输的大小，计算最大传输个数. Math.Ceiling 方法 (Double),返回大于或等于指定的双精度浮点数的最小整数值。 
  progressBar1.Maximum = max;//设置进度条的最大值
 int FileSize; //每次要拷贝的文件的大小
 if (TranSize < FormerOpenStream.Length)  //如果分段拷贝，即每次拷贝内容小于文件总长度
 {
     byte[] buffer = new byte[TranSize]; //根据传输的大小，定义一个字节数组，用来存储传输的字节
     int copied = 0;//记录传输的大小
     int tem_n = 1;//设置进度栏中进度的增加个数
     while (copied <= ((int)FormerOpenStream.Length - TranSize))
     {
  FileSize = FormerOpenStream.Read(buffer, 0, TranSize);//从0开始读到buffer字节数组中，每次最大读TranSize
  FormerOpenStream.Flush();   //清空缓存
  ToFileOpenStream.Write(buffer, 0, TranSize); //向目的文件写入字节
  ToFileOpenStream.Flush();//清空缓存
  ToFileOpenStream.Position = FormerOpenStream.Position; //是源文件的目的文件流的位置相同
  copied += FileSize; //记录已经拷贝的大小
  progressBar1.Value = progressBar1.Value + tem_n; //增加进度栏的进度块
     }
     int leftSize = (int)FormerOpenStream.Length - copied; //获取剩余文件的大小
     FileSize = FormerOpenStream.Read(buffer, 0, leftSize); //读取剩余的字节
     FormerOpenStream.Flush();
     ToFileOpenStream.Write(buffer, 0, leftSize); //写入剩余的部分
     ToFileOpenStream.Flush();
 }
 else //如果整体拷贝，即每次拷贝内容大于文件总长度
 {
     byte[] buffer = new byte[FormerOpenStream.Length];
     FormerOpenStream.Read(buffer, 0, (int)FormerOpenStream.Length);
     FormerOpenStream.Flush();
     ToFileOpenStream.Write(buffer, 0, (int)FormerOpenStream.Length);
     ToFileOpenStream.Flush(); 
  }
 FormerOpenStream.Close();
 ToFileOpenStream.Close();
 if (MessageBox.Show("copy finished") == DialogResult.OK)
 {
     progressBar1.Value = 0;
     txtOriginalFile.Clear();
     txtCopyFile.Clear();
     str = ""; 
  } 
     } 
     #endregion 
   
     public delegate void CopyFile_Delegate(); //定义委托/托管线程
    /// <summary>
    /// 在线程上执行委托（设置托管线程函数）
    /// </summary>
    public void SetCopyFile()
    {
 //this.Invoke(new CopyFile_Delegate(RunCopyFile)); //对指定的线程进行托管
 //下面两行代码等同上面一行代码
 CopyFile_Delegate copyfile_delegate = new CopyFile_Delegate(RunCopyFile); //创建delegate对象
 this.Invoke(copyfile_delegate); //调用delegate            
    } 
 
    /// <summary>
    /// 设置线程，运行copy文件，它与代理CopyFile_Delegate应具有相同的参数和返回类型
    /// </summary>
    public void RunCopyFile()
    {
 CopyFile(txtOriginalFile.Text, txtCopyFile.Text + "\\" + str, 1024, progressBar1); //复制文件
 Thread.Sleep(0); //避免假死 
 thdCopyFile.Abort();  //关闭线程 
     } 
 
    private void btnOriginalFile_Click(object sender, EventArgs e)
    {
 if (openFileDialog1.ShowDialog() == DialogResult.OK)  //打开文件对话框
 {
     txtOriginalFile.Text = openFileDialog1.FileName;  //获取源文件的路径
 } 
     } 
     private void btnCopyFile_Click(object sender, EventArgs e)
    {
 if (folderBrowserDialog1.ShowDialog() == DialogResult.OK)
 {
     txtCopyFile.Text = folderBrowserDialog1.SelectedPath;//获取目的文件的路径               
 }
    } 
 
    private void btnBeginToCopy_Click(object sender, EventArgs e)
    {                    

 if (txtOriginalFile.Text.Trim() == string.Empty)
 {
     MessageBox.Show("OriginalFile cannot be empty!");
     return;

 }
 else
 {
     str = txtOriginalFile.Text;//记录源文件的路径
     str = str.Substring(str.LastIndexOf('\\') + 1, str.Length - str.LastIndexOf('\\') - 1); //获取源文件的名称
 } 
 
 if (txtCopyFile.Text.Trim() == string.Empty)
 {
     MessageBox.Show("The Copyfile path cannot be empty!");
     return;
 }
 else
 {
     thdCopyFile = new Thread(new ThreadStart(SetCopyFile));
     thdCopyFile.Start();
 }             

    } 
 
    /// <summary>
    /// 给textbox增加tooltip
    /// </summary>
    /// <param name="sender"></param>
    /// <param name="e"></param>
    private void txtOriginalFile_MouseHover(object sender, EventArgs e)
    {
 ToolTip tooltip = new ToolTip();
 if (txtOriginalFile.Text.Trim() != string.Empty)
 {

     tooltip.Show(txtOriginalFile.Text, txtOriginalFile);
 }
 else
 {
     tooltip.Hide(txtOriginalFile);
 }

    }
    /// <summary>
    /// 给textbox增加tooltip
    /// </summary>
    /// <param name="sender"></param>
    /// <param name="e"></param>
    private void txtCopyFile_MouseHover(object sender, EventArgs e)
    {
 ToolTip tooltip = new ToolTip();
 if (txtCopyFile.Text.Trim() != string.Empty)
 {

     tooltip.Show(txtCopyFile.Text, txtCopyFile);
 }
 else
 {
     tooltip.Hide(txtCopyFile); 
 } 
     } 
 }
}