AddInToken.Activate<T> Method (AppDomain)


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Activates an add-in in an existing application domain.

Namespace:   System.AddIn.Hosting
Assembly:  System.AddIn (in System.AddIn.dll)

public T Activate<T>(
	AppDomain target


Type: System.AppDomain

The application domain that the add-in should be activated in.

Return Value

Type: T

The host view of the add-in.

Type Parameters


The interface or abstract base type that represents the host view of the add-in.

Exception Condition

Full-trust permission is demanded. A caller in the call chain does not have sufficient permission.

To activate an add-in in an automatically generated application domain, use the Activate<T>(AddInSecurityLevel) overload to generate a new application domain with a specified security level or the Activate<T>(AddInSecurityLevel, String) overload to include a friendly name for the application domain.

The following example activates an add-in in an application domain that is being used by another add-in. The code for the first add-in is provided in the AddInToken class.

// Get the application domain
// of an existing add-in (CalcAddIn).
AddInController aiCtrl = AddInController.GetAddInController(CalcAddIn);
AppDomain AddInAppDom = aiCtrl.AppDomain;

// Activate another add-in in the same application domain.
Calculator CalcAddIn3 =

// Show that CalcAddIn3 was loaded
// into CalcAddIn's application domain.
AddInController aic = AddInController.GetAddInController(CalcAddIn3);
Console.WriteLine("Add-in loaded into existing application domain: {0}",

.NET Framework
Available since 3.5
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