WPF多线程进度对话框 [英] WPF multithreaded progress dialog

问题描述

已更新这是一个有趣的问题。当后台进程运行时，我需要一个进度对话框显示。通常，这将工作，但问题是我需要在后台进程中设置公共静态数据。以下是我试图完成的一个例子：

Updated This is kind of an interesting problem I am experiencing. I need to have a progress dialog show when a background process is running. Normally, this would work but the problem is that I need to set public static data within the background process. Here is an example of what I am attempting to accomplish:

public partial class MainWindow : Window
{
    public static Service binding;
    public static Result lr;
    public progressDialog dlg;

    private void login()
    {
        string sPwd = txtPwd.Password;
        string sEmail = txtEmail.Text;
        binding = new Service();
        lr = binding.login(sEmail, sPwd);
    }
    private void btnLogin_Click(object sender, RoutedEventArgs e)
    {
        BackgroundWorker worker = new BackgroundWorker;
        worker.DoWork += new DoWorkEventHandler(worker_DoWork);
        worker.RunWorkerCompleted += new RunWorkerCompletedEventHandler(worker_RunWorkerCompleted)
        worker.RunWorkerAsync();
        dlg = new progressDialog();
        dlg.Show();
        login();
    }
    private void worker_DoWork(object sender, DoWorkEventArgs e)
    {
        e.Result = login();
    }
    private void worker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
    {
        this.Hid();
        Window1 newWindow = new Window1();
        newWindow.Show();
        dlg.Close();
    }

我知道这样做，因为login（）是一个void和在DoWork事件中实际没有返回一个与e.Result一起使用的值。但是，我已经设置了一个登录类来传递参数，我仍然收到错误，指出我无法访问UI线程。主要的问题是lr和绑定被另一个窗口访问，所以它们必须是公共静态数据（从另一个窗口我设置public static Service binding = MainWindow.binding;）。

I know that as this stands, it will not work because login() is a void and does not actually return a value to use with e.Result in the DoWork event. However, I have set up a login class to pass the parameters to and I still receive errors stating that I cannot access the UI thread. The main problem is that lr and binding are accessed by another window so they must be public static data (from the other window I set public static Service binding = MainWindow.binding;). I'm just having a bit of trouble wrapping my head around how exactly to set this up.

推荐答案

你需要阅读前台线程上的TextBoxes（txtEmail和txtPwd），而不是后台线程。这里有一个例子：

You need to read from the TextBoxes (txtEmail and txtPwd) on the foreground thread, not the background thread. Here's an example:

class MainWindow
{
  private string _email;
  private string _password;

  private void btnLogin_Click(...)
  {
    // running on UI thread here - can touch text boxes
    _email = txtEmail.Text;
    _password = txtPwd.Text;
    // ... set up worker ...
    worker.RunWorkerAsync();
  }

  private void login()
  {
    binding = new Service();
    // running on background thread here
    // but safe to access _email and _password they're just data, not UI controls
    lr = binding.login(_email, _password);
  }
}

编辑：更好，将电子邮件和密码作为参数传递，而不是将其存储在成员变量中：

Even better, pass the email and password as arguments rather than storing them in member variables:

  private void btnLogin_Click(...)
  {
    // running on UI thread here - can touch text boxes
    LoginInfo loginInfo = new LoginInfo(txtEmail.Text, txtPwd.Text);
    // ... set up worker ...
    worker.RunWorkerAsync(loginInfo);  // note argument
  }

  private void worker_DoWork(...)
  {
    LoginInfo loginInfo = (LoginInfo)(e.Argument);
    // now pass the LoginInfo to login() as an argument
  }

（并删除_email和_password成员）

(and remove the _email and _password members)

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