循环中的WPF应用程序,如何不冻结整个应用程序？

private async void Button_Click(object sender, RoutedEventArgs e)
{
    await Task.Run(() =>
    {
        for (int i = 0; i < 1000000; i++)
        {
            // 循环中的操作
        }
    });
}

private void Button_Click(object sender, RoutedEventArgs e)
{
    BackgroundWorker worker = new BackgroundWorker();
    worker.DoWork += (s, args) =>
    {
        for (int i = 0; i < 1000000; i++)
        {
            // 循环中的操作
        }
    };
    worker.RunWorkerAsync();
}

private void Button_Click(object sender, RoutedEventArgs e)
{
    Task.Run(() =>
    {
        for (int i = 0; i < 1000000; i++)
        {
            // 循环中的操作
            Dispatcher.Invoke(() =>
            {
                // 更新UI元素
            });
        }
    });
}

private ObservableCollection<string> items = new ObservableCollection<string>();
public ObservableCollection<string> Items
{
    get { return items; }
    set { items = value; }
}

private void Button_Click(object sender, RoutedEventArgs e)
{
    Task.Run(() =>
    {
        for (int i = 0; i < 1000000; i++)
        {
            // 循环中的操作
            Dispatcher.Invoke(() =>
            {
                // 更新UI元素
                Items.Add("New item");
            });
        }
    });
}