FileStream类操作文件

  private void buttonselect_Click (object sender, EventArgs e)         {             OpenFileDialog ofd = new OpenFileDialog();             ofd.Title = "请选择要复制的文件";             ofd.InitialDirectory = @"C:\Users\SpringRain\Desktop";             ofd.Filter = "所有文件|*.*";             ofd.ShowDialog();             textBoxSelect.Text = ofd.FileName;         }

        private void buttonsave_Click (object sender, EventArgs e)         {             SaveFileDialog sfd = new SaveFileDialog();             sfd.Title = "请选择要保存文件的路径";             sfd.InitialDirectory = @"C:\Users\SpringRain\Desktop";             sfd.Filter = "所有文件|*.*";             sfd.ShowDialog();             textBoxSave.Text = sfd.FileName;             //先读取 再写入             using (FileStream fsRead = new FileStream(textBoxSelect.Text.Trim(), FileMode.OpenOrCreate, FileAccess.Read))             {                 using (FileStream fsWrite = new FileStream(textBoxSave.Text.Trim(), FileMode.OpenOrCreate, FileAccess.Write))                 {                     //设置进度条                     progressBarFile.Maximum = (int)fsRead.Length;

                    byte[] buffer = new byte[1024 * 1024 * 3];                     while (true)                     {                         int r = fsRead.Read(buffer, 0, buffer.Length);                         if (r == 0)                         {                             break;                         }                         fsWrite.Write(buffer, 0, r);                         progressBarFile.Value = (int)fsWrite.Length;                     }

                    MessageBox.Show("保存成功");

                }             }