# IDTExtensibility2 Interface

Visual Studio 2013

Hosts the event notifications that occur to add-ins, such as when they are loaded, unloaded, updated, and so forth.

Namespace:  Extensibility
Assembly:  Extensibility (in Extensibility.dll)

## Syntax

```[GuidAttribute("B65AD801-ABAF-11D0-BB8B-00A0C90F2744")]
public interface IDTExtensibility2
```

The IDTExtensibility2 type exposes the following members.

## Methods

NameDescription
OnAddInsUpdateOccurs whenever an add-in is loaded or unloaded from the Visual Studio integrated development environment (IDE).
OnBeginShutdownOccurs whenever the Visual Studio integrated development environment (IDE) shuts down while an add-in is running.
OnConnectionOccurs whenever an add-in is loaded into Visual Studio.
OnDisconnectionOccurs whenever an add-in is unloaded from Visual Studio.
OnStartupCompleteOccurs whenever an add-in, which is set to load when Visual Studio starts, loads.
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## Remarks

IDTExtensibility2 contains methods that act as events when the interface is implemented. Visual Studio calls these methods whenever an event that affects an add-in occurs, such as when it is loaded or unloaded, whenever a change is made to it, and so forth.

## Examples

```public class Connect : Object, IDTExtensibility2
```