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JustInTimeActivationAttribute Class

Turns just-in-time (JIT) activation on or off. This class cannot be inherited.

Namespace:  System.EnterpriseServices
Assembly:  System.EnterpriseServices (in System.EnterpriseServices.dll)

<AttributeUsageAttribute(AttributeTargets.Class, Inherited := True)> _
<ComVisibleAttribute(False)> _
Public NotInheritable Class JustInTimeActivationAttribute _
	Inherits Attribute
Dim instance As JustInTimeActivationAttribute

If JIT activation is specified, then it must not be disabled in the COM+ catalog, and vice versa. If enabled in the COM+ catalog, it must be specified on the component.

JIT activation defaults to off for components which are configured in COM+, but is enabled automatically if automatic transactions are requested.

For more information about using attributes, see Extending Metadata Using Attributes.

The following code example demonstrates the use of this attribute.

Imports System
Imports System.EnterpriseServices
Imports System.Windows.Forms

<Assembly: ApplicationName("ObjectInspector")> 
<Assembly: ApplicationActivation(ActivationOption.Server)> 
<Assembly: System.Reflection.AssemblyKeyFile("Inspector.snk")> 

<JustInTimeActivation(), ObjectPooling(MinPoolSize := 2, MaxPoolSize := 100, CreationTimeout := 1000)>  _
Public Class ObjectInspector
    Inherits ServicedComponent

    Public Function IdentifyObject(ByVal obj As [Object]) As String  
        ' Return this object to the pool after use.
        ContextUtil.DeactivateOnReturn = True 

        ' Get the supplied object's type.         
        Dim objType As Type = obj.GetType()

        ' Return its name. 
        Return objType.FullName

    End Function 'IdentifyObject

    Protected Overrides Sub Activate() 
        MessageBox.Show(String.Format("Now entering..." + vbLf + "Application: {0}" + vbLf + "Instance: {1}" + vbLf + "Context: {2}" + vbLf, ContextUtil.ApplicationId.ToString(), ContextUtil.ApplicationInstanceId.ToString(), ContextUtil.ContextId.ToString()))

    End Sub 'Activate

    Protected Overrides Sub Deactivate() 
        MessageBox.Show("Bye Bye!")

    End Sub 'Deactivate

    ' This object can be pooled. 
    Protected Overrides Function CanBePooled() As Boolean  
        Return True 

    End Function 'CanBePooled

End Class 'ObjectInspector
#using <mscorlib.dll>
#using <System.Windows.Forms.dll>
#using <System.EnterpriseServices.dll>
using namespace System;
using namespace System::EnterpriseServices;
using namespace System::Windows::Forms;

[assembly: ApplicationName(S"ObjectInspector")]
[assembly: ApplicationActivation(ActivationOption::Server)]
[assembly: System::Reflection::AssemblyKeyFile(S"Inspector.snk")];

[ObjectPooling(MinPoolSize=2, MaxPoolSize=100, CreationTimeout=1000)]
public __gc class ObjectInspector : public ServicedComponent

    String* IdentifyObject (Object* obj)
        // Return this object to the pool after use.
        ContextUtil::DeactivateOnReturn = true;

        // Get the supplied object's type.        
        Type* objType = obj->GetType();

        // Return its name.


    void Activate()
        MessageBox::Show( String::Format(S"Now entering...\nApplication: {0}\nInstance: {1}\nContext: {2}\n",
                          ContextUtil::ApplicationId.ToString(), ContextUtil::ApplicationInstanceId.ToString(),
                          ContextUtil::ContextId.ToString() ) );

    void Deactivate()
        MessageBox::Show(S"Bye Bye!");

    // This object can be pooled.
    bool CanBePooled()



Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0