c#根据文件大小显示文件复制进度条实例_c#

初学者，照着书上的抄袭制作，但已经理解了里面的意思和应用,并且进行了稍微改善和异常捕捉。这里记录下，以防以后用到这方面的知识点。

窗体设计：

code:

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);
}