正确使用进度条

Question

这是我第一次在 C# 中使用进度条。 我的代码正在复制一些文件，我想通过进度条显示进度。

我不喜欢我的代码的一点是，我必须通过所有文件来设置栏的最大值……然后我再次通过相同的过程来复制文件。

如果不这样做，我就是想不出一种方法来确保在酒吧中顺利进行。我首先必须知道最大值对吗？还是有什么诀窍？

代码如下：

• 设置最大值：

  private static void setProgressBar(List<Source> sources, List<Destination> destinations)
  {
      progress.Value = 0;
      progress.Maximum = 0;
  
      foreach (var source in sources)
      {
          progress.Maximum += System.IO.Directory.GetDirectories(source.directory, "*",
              SearchOption.AllDirectories).Count() * destinations.Count +
              System.IO.Directory.GetFiles(source.directory, "*.*", SearchOption.AllDirectories).Count() *
              destinations.Count;
      }
  

• 复制文件：

  public static void CopyData(List<Source> sources, List<Destination> destinations, RichTextBox box, ProgressBar bar)
  {
      log = box;
      progress = bar;
      setProgressBar(sources, destinations);
  
      foreach (var source in sources)
      {
          foreach (var dirPath in System.IO.Directory.GetDirectories(source.directory, "*",
              SearchOption.AllDirectories))
          {
              foreach (var destination in destinations)
              {
                  logger(dirPath);
                  System.IO.Directory.CreateDirectory(dirPath.Replace(source.directory, destination.directory));
              }
          }
  
          foreach (var newPath in System.IO.Directory.GetFiles(source.directory, "*.*", SearchOption.AllDirectories))
          {
              foreach (var destination in destinations)
              {
                  logger(newPath);
                  File.Copy(newPath, newPath.Replace(source.directory, destination.directory), true);
              }
          }
      }
  }
  

• 增加进度条：

  私有静态无效记录器（字符串输出） { log.Text += "复制：" + 输出 + System.Environment.NewLine; log.SelectionStart = log.Text.Length; log.ScrollToCaret(); 进度.增量（1）； }

所以我两次运行相同的代码......我不喜欢这样:)

Answer 1

我在这里看到两个错误：您从未在 CopyData 方法中设置进度条的值 第二个是：您的 CopyData 方法将导致您的 UI 冻结，直到该方法完成（此时进度条将从 0 跳转到 100%）。

您可以将 CopyData 方法放在 BackgroundWorker 中并调用 ReportProgress 并在 ReportProgress 事件中设置栏的新值。

这是一个如何完成的示例。而不是static void Main(..) 调用工作人员，您将从那里开始您的 CopyData 方法

static void Main(string[] args)
{
    System.ComponentModel.BackgroundWorker worker = new System.ComponentModel.BackgroundWorker();
    worker.ProgressChanged += Worker_ProgressChanged;
    worker.DoWork += Worker_DoWork;

    //Do work
    worker.RunWorkerAsync();
}

private static void Worker_DoWork(object sender, System.ComponentModel.DoWorkEventArgs e)
{
    //Get Values
    var source = null;
    var destinations = null;

    //CopyData Method
    setProgressBar(sources, destinations);
    foreach (var source in sources)
    {
        foreach (var dirPath in System.IO.Directory.GetDirectories(source.directory, "*", SearchOption.AllDirectories))
        {
            foreach (var destination in destinations)
            {
                logger(dirPath);
                System.IO.Directory.CreateDirectory(dirPath.Replace(source.directory, destination.directory));
                //Increase Value by 1
                (sender as System.ComponentModel.BackgroundWorker).ReportProgress(1);
            }
        }

        foreach (var newPath in System.IO.Directory.GetFiles(source.directory, "*.*", SearchOption.AllDirectories))
        {
            foreach (var destination in destinations)
            {
                logger(newPath);
                File.Copy(newPath, newPath.Replace(source.directory, destination.directory), true);
                //Increase Value by 1
                (sender as System.ComponentModel.BackgroundWorker).ReportProgress(1);
            }
        }
    }
}

private static void Worker_ProgressChanged(object sender, System.ComponentModel.ProgressChangedEventArgs e)
{
    if (e.ProgressPercentage == 1)
    {
        //If Value gets higher than Maximum it will cause an Exception
        if (progress.Value < progress.Maximum)
            progress.Value += 1;
    }
}

private static void setProgressBar(List sources, List destinations)
{
    progress.Value = 0;
    progress.Maximum = 0;
    foreach (var source in sources)
    {
        foreach (var dirPath in System.IO.Directory.GetDirectories(source.directory, "*", SearchOption.AllDirectories))
        {
            //Simplified
            progress.Maximum += destinations.Count;
        }

        foreach (var newPath in System.IO.Directory.GetFiles(source.directory, "*.*", SearchOption.AllDirectories))
        {
            //Simplified
            progress.Maximum += destinations.Count;
        }
    }
}