后台工作人员完成事件在实际完成工作之前触发

Question

在我的应用程序中，当用户单击菜单项时，系统会提示他们 select 一个文件，然后我使用后台工作程序加载和解析，在此期间将进度报告给进度条手术。工作完成后，我开始一个新的 window 并将解析后的数据传递给它。出于某种原因，新的 window 在数据被解析并传递空参数而不是数据之前被打开。

我的点击事件：

private void CIRCUIT_INSTALATION_SCHEDULED_Click(object sender, RoutedEventArgs e)
{
    //prevents users from selecting other menu items 
    disableAll();

    System.Windows.Forms.OpenFileDialog mainExcelFileDialog = new System.Windows.Forms.OpenFileDialog();
    mainExcelFileDialog.InitialDirectory = System.Configuration.ConfigurationManager.AppSettings["MainWorkbookDirectory"];
    mainExcelFileDialog.Title = "Main Excel File";
    mainExcelFileDialog.ShowDialog();
    string mainPath = mainExcelFileDialog.FileName;
    this.Cursor = System.Windows.Input.Cursors.Wait;
    BackgroundWorker cisWorker = new BackgroundWorker();

    cisWorker.DoWork += cisWorker_DoWork;
    cisWorker.ProgressChanged+=cisWorker_ProgressChanged;
    cisWorker.RunWorkerCompleted += cisWorker_RunWorkerCompleted;            
    cisWorker.RunWorkerAsync(mainPath);            
}

我的工作：

void cisWorker_DoWork(object sender, DoWorkEventArgs e)
{            
    BackgroundWorker worker = sender as BackgroundWorker;
    using (FileStream fs = new FileStream(e.Argument.ToString() , FileMode.Open))
    {
        //copy filestream to memorystream chunk by chunk, reporting progress.
        using (MemoryStream ms = new MemoryStream())
        {
            byte[] buffer = new byte[32768];
            int read;
            int steps = Convert.ToInt32(fs.Length / buffer.Length);
            int i = 0;
            while ((read = fs.Read(buffer, 0, buffer.Length)) > 0)
            {

                ms.Write(buffer, 0, read);
                i++;
                var progress = new Decimal(i) / new Decimal(steps);
                var outOf = Math.Round(progress * 50);
                worker.ReportProgress(Convert.ToInt32(outOf));
            }

            worker.ReportProgress(50);
            ms.Position = 0;
            //load excel workbook dataset from memorystream
            using (var xlr = Excel.ExcelReaderFactory.CreateOpenXmlReader(ms))
            {
                xlr.IsFirstRowAsColumnNames = true;
                mainWorkbook = xlr.AsDataSet();
                worker.ReportProgress(100);

            }

        }
    }
}

我的完成：

void cisWorker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
    this.Cursor = System.Windows.Input.Cursors.Arrow;
    CircuitInstallationScheduledWindow CIS_Window = new CircuitInstallationScheduledWindow();
    CIS_Window.Show();
    CIS_Window.Closed += CIS_Window_Closed;
}

编辑：我将 mainPath 参数添加到 cisWorker.runWorkerAsync() 方法。不幸的是，问题仍然存在。

Answer 1

Henk Holterman 是对的。我收到一个错误，因为我没有设置 cisWorker.WorkerReportsProgress = true; 我仍然不知道为什么错误没有破坏调试器，因为它没有被处理，但是我在我的 Completed 方法中做了一个打印语句，这有助于我追查罪魁祸首。

void cisWorker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
    {
        Console.WriteLine(e.Error);
        this.Cursor = System.Windows.Input.Cursors.Arrow;
        CircuitInstallationScheduledWindow CIS_Window = new CircuitInstallationScheduledWindow(mainWorkbook, abfsDatabase);
        CIS_Window.Show();
        CIS_Window.Closed += CIS_Window_Closed;
    }

Answer 2

基本上你应该检查你的数据是否为空，即在 DoWork 期间没有发生错误

void cisWorker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
    if (e.Error == null)
    {
        /* Your mainWorkbook shouldn't be null */

        this.Cursor = System.Windows.Input.Cursors.Arrow;
        CircuitInstallationScheduledWindow CIS_Window = new CircuitInstallationScheduledWindow();
        CIS_Window.Show();
        CIS_Window.Closed += CIS_Window_Closed;
    }
    else
    {
        // Handle error
    }
}

后台工作人员完成事件在实际完成工作之前触发

Background Worker Completed Event is firing before it is actually finished doing work

c#

events

backgroundworker