没有调用BackgroundWorker DoWork函数

Question

我在C#WinForms应用程序中创建了一个加载表单，该表单在长进程中显示。我在我的加载表单中添加了一个进度条，我想更新它，以便向用户提供一些加载反馈。

在我的加载表单代码中，我创建了一个新的BackgroundWorker，并添加了DoWork和ProgressChanged事件处理程序。问题是没有调用backgroundWorker_ProgressChanged。我在函数中插入了断点，但它们没有被捕获。

我哪里错了？感谢您的帮助。谢谢

frm加载：

public frmLoading()
{
InitializeComponent();
//check if bg worker is null
if (backgroundWorker == null)
{
backgroundWorker = new BackgroundWorker();
backgroundWorker.DoWork += backgroundWorker_DoWork;
backgroundWorker.ProgressChanged += backgroundWorker_ProgressChanged;

}
backgroundWorker.WorkerReportsProgress = true;
//start
backgroundWorker.RunWorkerAsync();
}

backgroundWorker_DoWork：

private void backgroundWorker_DoWork(object sender, DoWorkEventArgs e)
{
for (int i = 1; i <= 100; i++)
{
Thread.Sleep(100);
backgroundWorker.ReportProgress(i);
}
}

backgroundWorker_ProgressChanged:

private void backgroundWorker_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
//update value of progress bar
progressBar1.Value = e.ProgressPercentage;
//set the text of the progress bar
this.Text = e.ProgressPercentage.ToString();
}

Answer 1

以下是如何使用Progress<int>和Task.Run:

public frmLoading()
{
InitializeComponent();
IProgress<int> progress = new Progress<int>(p =>
{
//update value of progress bar
progressBar1.Value = p;
//set the text of the progress bar
this.Text = p.ToString();
});
Task.Run(async () =>
{
for (int i = 1; i <= 100; i++)
{
await Task.Delay(TimeSpan.FromSeconds(0.1));
progress.Report(i);
}
});
}

---

就我个人而言，我更喜欢微软的反应式框架：

public frmLoading()
{
InitializeComponent();
Observable
.Interval(TimeSpan.FromSeconds(0.1))
.Take(100)
.ObserveOn(this)
.Select(p => p + 1)
.Subscribe(p =>
{
//update value of progress bar
progressBar1.Value = p;
//set the text of the progress bar
this.Text = p.ToString();
});
}