ObjectPoolingAttribute Class

Reference

Definition

Namespace:: System.EnterpriseServices

Assembly:: System.EnterpriseServices.dll

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Enables and configures object pooling for a component. This class cannot be inherited.

public ref class ObjectPoolingAttribute sealed : Attribute

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

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

Public NotInheritable Class ObjectPoolingAttribute
Inherits Attribute

Inheritance: Object

Attribute
ObjectPoolingAttribute

Attributes: AttributeUsageAttribute ComVisibleAttribute

Examples

The following code example demonstrates the use of this attribute.

#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

Remarks

If object pooling is specified, it must not be disabled in the COM+ catalog; if enabled in the COM+ catalog, it must be specified on the component.

For a list of initial property values for an instance of ObjectPoolingAttribute, see the ObjectPoolingAttribute constructor.

For more information about using attributes, see Attributes.

Constructors

ObjectPoolingAttribute()	Initializes a new instance of the ObjectPoolingAttribute class and sets the Enabled, MaxPoolSize, MinPoolSize, and CreationTimeout properties to their default values.
ObjectPoolingAttribute(Boolean, Int32, Int32)	Initializes a new instance of the ObjectPoolingAttribute class and sets the Enabled, MaxPoolSize, and MinPoolSize properties.
ObjectPoolingAttribute(Boolean)	Initializes a new instance of the ObjectPoolingAttribute class and sets the Enabled property.
ObjectPoolingAttribute(Int32, Int32)	Initializes a new instance of the ObjectPoolingAttribute class and sets the MaxPoolSize and MinPoolSize properties.

Properties

CreationTimeout	Gets or sets the length of time to wait for an object to become available in the pool before throwing an exception. This value is in milliseconds.
Enabled	Gets or sets a value that indicates whether object pooling is enabled.
MaxPoolSize	Gets or sets the value for the maximum size of the pool.
MinPoolSize	Gets or sets the value for the minimum size of the pool.
TypeId	When implemented in a derived class, gets a unique identifier for this Attribute. (Inherited from Attribute)

Methods

AfterSaveChanges(Hashtable)	Called internally by the .NET Framework infrastructure while installing and configuring assemblies in the COM+ catalog.
Apply(Hashtable)	Called internally by the .NET Framework infrastructure while applying the ObjectPoolingAttribute class attribute to a serviced component.
Equals(Object)	Returns a value that indicates whether this instance is equal to a specified object. (Inherited from Attribute)
GetHashCode()	Returns the hash code for this instance. (Inherited from Attribute)
GetType()	Gets the Type of the current instance. (Inherited from Object)
IsDefaultAttribute()	When overridden in a derived class, indicates whether the value of this instance is the default value for the derived class. (Inherited from Attribute)
IsValidTarget(String)	Called internally by the .NET Framework infrastructure while installing and configuring assemblies in the COM+ catalog.
Match(Object)	When overridden in a derived class, returns a value that indicates whether this instance equals a specified object. (Inherited from Attribute)
MemberwiseClone()	Creates a shallow copy of the current Object. (Inherited from Object)
ToString()	Returns a string that represents the current object. (Inherited from Object)

Explicit Interface Implementations

_Attribute.GetIDsOfNames(Guid, IntPtr, UInt32, UInt32, IntPtr)	Maps a set of names to a corresponding set of dispatch identifiers. (Inherited from Attribute)
_Attribute.GetTypeInfo(UInt32, UInt32, IntPtr)	Retrieves the type information for an object, which can be used to get the type information for an interface. (Inherited from Attribute)
_Attribute.GetTypeInfoCount(UInt32)	Retrieves the number of type information interfaces that an object provides (either 0 or 1). (Inherited from Attribute)
_Attribute.Invoke(UInt32, Guid, UInt32, Int16, IntPtr, IntPtr, IntPtr, IntPtr)	Provides access to properties and methods exposed by an object. (Inherited from Attribute)

Applies to

แชร์ผ่าน