Question

我有一个背景工作者：

private readonly BackgroundWorker _importWorker = new BackgroundWorker() { WorkerReportsProgress = true };

在我的构造函数中，我做了：

_importWorker.DoWork += _importWorker_DoWork;
_importWorker.ProgressChanged += _importWorker_ProgressChanged;
_importWorker.RunWorkerCompleted += _importWorker_RunWorkerCompleted;

以下是代表：

private void _importWorker_DoWork(object sender, DoWorkEventArgs e)
    {
        var args = (object[]) e.Argument;
        var walletColumnName = (string) args[0];
        var fundColumnName = (string) args[1];
        var isinColumName = (string) args[2];
        var marketValueDirtyColumnName = (string) args[3];
        var seperator = (string) args[4];
        var importFilePath = (string) args[5];
        var importFile = Path.GetFileName(importFilePath);

        var onePercent = 100.0 / File.ReadLines(importFilePath).Count();
        var totalPercentage = 0.0;


        var parser = new TextFieldParser(importFilePath);
        parser.TextFieldType = FieldType.Delimited;
        parser.SetDelimiters(seperator);

        //Read colum indexes on the first line
        var fields = parser.ReadFields();
        var walletColumnIndex = Array.IndexOf(fields, walletColumnName);
        var fundColomnIndex = Array.IndexOf(fields, fundColumnName);
        var isinColumnIndex = Array.IndexOf(fields, isinColumName);
        var marketValueDirtyColumnIndex = Array.IndexOf(fields, marketValueDirtyColumnName);

        if (walletColumnIndex == -1 || fundColomnIndex == -1 || isinColumnIndex == -1 ||
            marketValueDirtyColumnIndex == -1)
        {
            throw new ArgumentException("Eén of meerdere kolommen niet gevonden in " + importFile);
        }

        //TODO

        e.Result = importFile;     
    }

    private void _importWorker_ProgressChanged(object sender, ProgressChangedEventArgs e)
    {
        Progress = e.ProgressPercentage;
    }

    private void _importWorker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
    {
        if (e.Error != null)
        {
            Messenger.Default.Send(e.Error);
        }

        else if (e.Result != null)
        {
            PenultimateImportFileName = LastImportFileName;
            PenultimateImportDate = LastImportDate;               
            LastImportFileName = e.Result.ToString();
            LastImportDate = ImportDate;
            _dataContainer.UpdateImportSettings(_importSettings);
        }

        Progress = 100;
        IsBusy = false;
    }

当抛出异常时，backroundworker不会调用e.Error，而是应用程序崩溃。这是正常的，如何解决？我读到当在dowork中抛出未处理的异常时，会自动调用E.Error。

这就是我称之为背景工作者的方式：

_importWorker.RunWorkerAsync(new object[] {WalletColumnName, FundColumnName, IsinColumName, MarketValueDirtyColumnName, Seperator, s});

修改

调试器会中断并抛出我抛出代码的异常：

System.ArgumentException was unhandled by user code
  HResult=-2147024809
  Message=Eén of meerdere kolommen niet gevonden in 021214-0.txt
  Source=Selection Monitoring Tool
  StackTrace:
       at Selection_Monitoring_Tool.ViewModels.SettingsViewModel._importWorker_DoWork(Object sender, DoWorkEventArgs e) in c:\Users\Joost\Desktop\Selection Monitoring Tool\Selection Monitoring Tool\ViewModels\SettingsViewModel.cs:line 216
       at System.ComponentModel.BackgroundWorker.OnDoWork(DoWorkEventArgs e)
       at System.ComponentModel.BackgroundWorker.WorkerThreadStart(Object argument)
  InnerException:

Answer 1

正如@HansPassant建议的那样，我必须取消选中“当这个例外类型是用户unhandeled时中断”复选框。

抛出异常时，C＃Backgroundwork不会调用e.Error

修改

1 个答案: