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，我必须遍历所有文件来设置最大值...后来我再次经历同样的过程来复制文件。

我只是想不出一个方法来确保在酒吧里流利的进步而不这样做。我首先必须知道最大值对吗？或者有什么诀窍吗？

代码如下所示：

>

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=“Copy:”输出System.Environment.NewLine；log.SelectionStart=log.Text.Length；log.ScrollToCaret（）；progress.Increment（1）；}

所以我运行相同的代码两次...

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，第二个错误是：您的CopyData方法将导致您的用户界面冻结，直到方法完成（当时进度条将从0跳到100%）。

您可以将CopyData方法放在BackgroundWorker中，调用ReportProgress，并在ReportProgress事件中设置条形图的新值。

下面是一个如何完成的例子。调用工作人员，而不是静态无效Main（...），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;
        }
    }
}