Question

public partial class MainPage : UserControl
{
private MapLayer m_PushpinLayer;

public MainPage()
{
    InitializeComponent();
    base.Loaded += OnLoaded;
}

private void OnLoaded(object sender, RoutedEventArgs e)
{
    base.Loaded -= OnLoaded;

m_PushpinLayer = new MapLayer();
x_Map.Children.Add(m_PushpinLayer);
    x_Map.MouseClick += OnMouseClick;
}

In above code what does base.loaded += Onloaded as well as base.loaded -= onloaded means ?

Thnks in advance for your reply

Answer 1

This code basically attached a function OnLoaded to the Loaded event on the base class.
Essentially, when the Loaded event occurs, the OnLoaded function handles it.
The += attaches the handler to the event, the -= removes the handler from the event.

Check this http://msdn.microsoft.com/en-us/library/awbftdfh.aspx.
It may help you understand events.