How to dismiss a MessageDialog from code in Windows Phone 8.1

问题

How can I dismiss a Message dialog programmatically in Windows Phone 8.1. I created the dialog using showAsync(). If this is not possible which is the best method to create a custom message dialog with the following properties:

1. It can show test and hold buttons for user interaction.
2. It can be dismissed programmatically
3. Should block the view as a Normal MessageDialog do

回答1:

Use a ContentDialog rather than a MessageDialog. This will also allow customizing the dialog so you don't need to write a custom control unless you want to do something really crazy.

On Windows the MessageDialog is cancellable, but not on Windows Phone:

// Cancel the MessageDialog after 3 seconds on Windows
private async void Button_Click(object sender, RoutedEventArgs e)
{
    MessageDialog md = new MessageDialog("Lorem ipsum dolor sit amet","Message Dialog Title");
    var t = md.ShowAsync();

    await Task.Delay(TimeSpan.FromSeconds(3));

    // Ignored by the Windows Phone MessageDialog
    t.Cancel();
}

You can cancel ContentDialog with similar code on Windows Phone. You can use Visual Studio's ContentDialog template to create a custom ContentDialog if needed.

private async void Button_Click(object sender, RoutedEventArgs e)
{
    ContentDialog cd = new ContentDialog();
    cd.Title = "Content Dialog";
    cd.PrimaryButtonText = "Close";
    cd.Content = "Lorem ipsum dolor sit amet";
    var t = cd.ShowAsync();

    await Task.Delay(TimeSpan.FromSeconds(3));

    t.Cancel();
}

来源：https://stackoverflow.com/questions/28795850/how-to-dismiss-a-messagedialog-from-code-in-windows-phone-8-1