c# - 使用BackgroundWorker的请求似乎永远不会完成

Question

我为登录表单创建了一个加载窗口，并使用BackgroundWorker制作平滑的加载动画，但是如果我使用ShowDialog()而不是Show() ，加载窗口停留在屏幕上，程序不执行任何操作。这是什么原因造成的？

这里我调用BackgroundWorker并显示加载页面:

private void loginButton_Click(object sender, EventArgs e) {
    loadscr.Show();
    LoginBV.RunWorkerAsync();
}

这里我关闭加载窗口:

private void LoginBV_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e) {
    loadscr.Close();
    //and show the MainWindow, etc.
}

DoWork(BackgroundWorker)代码:

    private void LoginBV_DoWork(object sender, DoWorkEventArgs e) {
        NameValueCollection POST = new NameValueCollection();
        POST["username"] = ipbUN.Text;
        POST["password"] = ipbPASS.Text;
        POST["pin"] = ipbPIN.Text;
        POST["csoport"] = "user";

        var action = Program.startPOST<DataObj>("http://localhost/system/winapi.php?do=userlogin", POST);

        finish["sessionkey"] = action.sessionkey;
        finish["status"] = Convert.ToString(action.status);
    }

Answer 1

参见MSDN article on ShowDialog .

"You can use this method to display a modal dialog box in your application. When this method is called, the code following it is not executed until after the dialog box is closed."

使用模态对话框 (ShowDialog) 会停止执行其后面的代码，直到某物/某人关闭该对话框。它“暂停”你的程序。后台工作程序永远不会运行，因为您在调用 ShowDialog 后启动它。