c# - 用户的 SharpBox 进度条

Question

我试图在上传文件期间向用户显示进度条。我可以通过以下方法在后端获取百分比，但是我无法打印 e.PercentageProgress 返回的百分比以显示给用户。

  static void UploadDownloadProgress(Object sender, FileDataTransferEventArgs e)
  {
        // Need to show this on a label or return to front end somehow
        System.Diagnostics.Debug.WriteLine(e.PercentageProgress);            

        e.Cancel = false;
  }

问题是如何让 e.PercentageProgress 显示在 aspx 页面上或让它在 javascript 中使用？

Answer 1

尝试这样的事情:

public class ProgressInformer {

    public static string Progress = "0";

    static void UploadDownloadProgress(Object sender, FileDataTransferEventArgs e)
    {

        // print a dot           
        System.Diagnostics.Debug.WriteLine(e.PercentageProgress);

        // Need to show this on a label or return to front end somehow
        ProgressInformer.Progress = e.PercentageProgress.ToString();

        e.Cancel = false;
    }
}

现在，由于您正在为静态变量设置值，因此您可以从其他地方访问它。然后您可以使用该值通过某种方法或服务在前端回显。可能是这样的:

public string EchoToFrontEnd()
{
    return ProgressInformer.Progress;
}

Limitation: If this works for you still this solution is not thread safe. That means, you cannot echo progress for multiple downloads. You'll have to work with a single download at a time.

希望这有助于...!