对于没有触发的BackgroundWorker事件感到困惑

这可能看起来像一个有点人为的例子,但我只是在挠头.

好的,我有一个控制台应用程序,它实例化一个WindowsForm并在窗体上调用一个名为DoSomeWork()的方法.

class Program
  { 
    static void Main(string[] args)
    {
      Form1 form = new Form1();         
      form.DoSomeWork();   
    }
  }

Form1看起来像这样......

public partial class Form1 : Form
  {
    public Form1()
    {
      InitializeComponent();
    }

    public void DoSomeWork()
    {
      OuterClass outerClass = new OuterClass();
      outerClass.DoSomeWork();
    }    
  }

反过来,外类看起来像......

public class OuterClass
  {
    public void DoSomeWork()
    {
      InnerClass innerClass = new InnerClass();
      innerClass.DoSomeWork();
    }
  }

最后,InnerClass看起来像这样......

public class InnerClass
  {
    private BackgroundWorker _backgroundWorker = new BackgroundWorker();

    public InnerClass()
    {
      _backgroundWorker.WorkerReportsProgress = true;
      _backgroundWorker.DoWork += new DoWorkEventHandler(BackgroundWorker_DoWork);
      _backgroundWorker.ProgressChanged += new ProgressChangedEventHandler(BackgroundWorker_ProgressChanged);
    }

    void BackgroundWorker_ProgressChanged(object sender, ProgressChangedEventArgs e)
    {
      int i = 0; //I've placed a break point here. But it's never hit
    }

    void BackgroundWorker_DoWork(object sender, DoWorkEventArgs e)
    {
      BackgroundWorker worker = sender as BackgroundWorker;

      worker.ReportProgress(42);
    }

    public void DoSomeWork()
    {
      _backgroundWorker.RunWorkerAsync();
    }
  }

由于一个未知的原因(对我而言),InnerClass中的BacgroundWorker似乎永远不会触发ProgressChanged事件.如果我更换

Form1 form = new Form1();

同

OuterClass outerClass = new OuterClass()

在课程计划中,它工作正常.那么,当我通过表单调用相同的方法时,为什么我的事件不会触发？

谢谢!

编辑:我似乎是通过将ProgressChanged事件处理程序保留为抛出NotImplementedException来抛弃人员,所以我为了清楚起见删除了它.

您忘记启动消息循环,需要调用Application.Run().如果没有消息循环,BackgroundWorker事件将无法工作.修理:

static void Main(string[] args)
{
  Application.Run(new Form1());   
}

在窗体的构造函数中调用DoSomeWork()或它的Load事件.