JustInTimeActivationAttribute 類別

定義

public ref class JustInTimeActivationAttribute sealed : Attribute

[System.AttributeUsage(System.AttributeTargets.Class, Inherited=true)]
[System.Runtime.InteropServices.ComVisible(false)]
public sealed class JustInTimeActivationAttribute : Attribute

[<System.AttributeUsage(System.AttributeTargets.Class, Inherited=true)>]
[<System.Runtime.InteropServices.ComVisible(false)>]
type JustInTimeActivationAttribute = class
    inherit Attribute

Public NotInheritable Class JustInTimeActivationAttribute
Inherits Attribute

繼承

Object

Attribute

JustInTimeActivationAttribute

屬性

AttributeUsageAttribute ComVisibleAttribute

範例

以下程式碼範例示範此屬性的使用。

#using <System.Windows.Forms.dll>
#using <System.Transactions.dll>
#using <System.EnterpriseServices.dll>

using namespace System;
using namespace System::EnterpriseServices;
using namespace 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 ref class ObjectInspector: public ServicedComponent
{
public:
   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.
      return (objType->FullName);
   }

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

   virtual void Deactivate() override
   {
      MessageBox::Show( "Bye Bye!" );
   }

   // This object can be pooled.
   virtual bool CanBePooled() override
   {
      return (true);
   }
};

using System;
using System.EnterpriseServices;
using 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 : ServicedComponent
{

    public 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.
        return(objType.FullName);
    }

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

    protected override void Deactivate()
    {
        MessageBox.Show("Bye Bye!");
    }

    // This object can be pooled.
    protected override bool CanBePooled()
    {
        return(true);
    }
}

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

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

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

End Class

備註

若指定 JIT 啟用，則在 COM+ 目錄中不得停用，反之亦然。 若在 COM+ 目錄中啟用，則必須在元件上指定。

對於在 COM+ 中設定的元件，JIT 啟用預設為關閉，但若請求自動交易，則會自動啟用。

欲了解更多屬性的使用資訊，請參閱屬性。