IInstanceProvider.GetInstance Methode

Definitie

Retourneert een serviceobject.

Overloads

Name Description
GetInstance(InstanceContext)

Retourneert een serviceobject op basis van het opgegeven InstanceContext object.

GetInstance(InstanceContext, Message)

Retourneert een serviceobject op basis van het opgegeven InstanceContext object.

GetInstance(InstanceContext)

Retourneert een serviceobject op basis van het opgegeven InstanceContext object.

public:
 System::Object ^ GetInstance(System::ServiceModel::InstanceContext ^ instanceContext);
public object GetInstance(System.ServiceModel.InstanceContext instanceContext);
abstract member GetInstance : System.ServiceModel.InstanceContext -> obj
Public Function GetInstance (instanceContext As InstanceContext) As Object

Parameters

instanceContext
InstanceContext

Het huidige InstanceContext object.

Retouren

Een door de gebruiker gedefinieerd serviceobject.

Voorbeelden

In het volgende codevoorbeeld ziet u hoe u implementeert IInstanceProvider dat 'singleton'-gedrag biedt. Het retourneert altijd hetzelfde service-exemplaar en recyclet het niet.

public class ObjectProviderBehavior : IInstanceProvider
{

  string message;
  SampleService service = null;

  public ObjectProviderBehavior(string msg)
  {
    Console.WriteLine("The non-default constructor has been called.");
    this.message = msg;
    this.service = new SampleService("Singleton sample service.");
  }

  #region IInstanceProvider Members

  public object GetInstance(InstanceContext instanceContext, System.ServiceModel.Channels.Message message)
  {
    Console.WriteLine("GetInstance is called:");
    return this.service;
  }

  public object GetInstance(InstanceContext instanceContext)
  {
    Console.WriteLine("GetInstance is called:");
    return this.service;
  }

  public void ReleaseInstance(InstanceContext instanceContext, object instance)
  {
    Console.WriteLine("ReleaseInstance is called. The SingletonBehaviorAttribute never releases.");
  }

  #endregion
}
Public Class ObjectProviderBehavior
    Implements IInstanceProvider

  Private message As String
  Private service As SampleService = Nothing

  Public Sub New(ByVal msg As String)
    Console.WriteLine("The non-default constructor has been called.")
    Me.message = msg
    Me.service = New SampleService("Singleton sample service.")
  End Sub

  #Region "IInstanceProvider Members"

  Public Function GetInstance(ByVal instanceContext As InstanceContext, ByVal message As System.ServiceModel.Channels.Message) As Object Implements IInstanceProvider.GetInstance
    Console.WriteLine("GetInstance is called:")
    Return Me.service
  End Function

  Public Function GetInstance(ByVal instanceContext As InstanceContext) As Object Implements IInstanceProvider.GetInstance
    Console.WriteLine("GetInstance is called:")
    Return Me.service
  End Function

  Public Sub ReleaseInstance(ByVal instanceContext As InstanceContext, ByVal instance As Object) Implements IInstanceProvider.ReleaseInstance
    Console.WriteLine("ReleaseInstance is called. The SingletonBehaviorAttribute never releases.")
  End Sub

  #End Region
End Class

In het volgende codevoorbeeld ziet u hoe u een aangepast kenmerk implementeert dat wordt geïmplementeerd IContractBehavior om de provider van het aangepaste service-exemplaar in te voegen. Het implementeert IContractBehaviorAttributeook , waarmee het gebruik wordt gebonden aan een specifiek contract.

public class SingletonBehaviorAttribute : Attribute, IContractBehaviorAttribute, IContractBehavior
{

  #region IContractBehaviorAttribute Members

  public Type TargetContract
  {
    get { return typeof(ISampleService); }
  }

  #endregion

  #region IContractBehavior Members

  public void AddBindingParameters(ContractDescription description, ServiceEndpoint endpoint, System.ServiceModel.Channels.BindingParameterCollection parameters)
  {
    return;
  }

  public void ApplyClientBehavior(ContractDescription description, ServiceEndpoint endpoint, ClientRuntime clientRuntime)
  {
    return;
  }

  public void ApplyDispatchBehavior(ContractDescription description, ServiceEndpoint endpoint, DispatchRuntime dispatch)
  {
    dispatch.InstanceProvider = new ObjectProviderBehavior("Custom ObjectProviderBehavior constructor.");
  }

  public void Validate(ContractDescription description, ServiceEndpoint endpoint)
  {
    return;
  }

  #endregion
}
Public Class SingletonBehaviorAttribute
    Inherits Attribute
    Implements IContractBehaviorAttribute, IContractBehavior

  #Region "IContractBehaviorAttribute Members"

  Public ReadOnly Property TargetContract() As Type Implements IContractBehaviorAttribute.TargetContract
    Get
        Return GetType(ISampleService)
    End Get
  End Property

  #End Region

  #Region "IContractBehavior Members"

  Public Sub AddBindingParameters(ByVal description As ContractDescription, ByVal endpoint As ServiceEndpoint, ByVal parameters As System.ServiceModel.Channels.BindingParameterCollection) Implements IContractBehavior.AddBindingParameters
    Return
  End Sub

  Public Sub ApplyClientBehavior(ByVal description As ContractDescription, ByVal endpoint As ServiceEndpoint, ByVal clientRuntime As ClientRuntime) Implements IContractBehavior.ApplyClientBehavior
    Return
  End Sub

  Public Sub ApplyDispatchBehavior(ByVal description As ContractDescription, ByVal endpoint As ServiceEndpoint, ByVal dispatch As DispatchRuntime) Implements IContractBehavior.ApplyDispatchBehavior
    dispatch.InstanceProvider = New ObjectProviderBehavior("Custom ObjectProviderBehavior constructor.")
  End Sub

  Public Sub Validate(ByVal description As ContractDescription, ByVal endpoint As ServiceEndpoint) Implements IContractBehavior.Validate
    Return
  End Sub

  #End Region
End Class

Opmerkingen

Gebruik de GetInstance(InstanceContext) methode om het exacte serviceobject te bepalen dat een WCF-service ontvangt wanneer er een nieuwe wordt gemaakt.

Van toepassing op

GetInstance(InstanceContext, Message)

Retourneert een serviceobject op basis van het opgegeven InstanceContext object.

public:
 System::Object ^ GetInstance(System::ServiceModel::InstanceContext ^ instanceContext, System::ServiceModel::Channels::Message ^ message);
public object GetInstance(System.ServiceModel.InstanceContext instanceContext, System.ServiceModel.Channels.Message message);
abstract member GetInstance : System.ServiceModel.InstanceContext * System.ServiceModel.Channels.Message -> obj
Public Function GetInstance (instanceContext As InstanceContext, message As Message) As Object

Parameters

instanceContext
InstanceContext

Het huidige InstanceContext object.

message
Message

Het bericht dat het maken van een serviceobject heeft geactiveerd.

Retouren

Het serviceobject.

Voorbeelden

In het volgende codevoorbeeld ziet u hoe u implementeert IInstanceProvider dat 'singleton'-gedrag biedt. Het retourneert altijd hetzelfde service-exemplaar en recyclet het niet.

public class ObjectProviderBehavior : IInstanceProvider
{

  string message;
  SampleService service = null;

  public ObjectProviderBehavior(string msg)
  {
    Console.WriteLine("The non-default constructor has been called.");
    this.message = msg;
    this.service = new SampleService("Singleton sample service.");
  }

  #region IInstanceProvider Members

  public object GetInstance(InstanceContext instanceContext, System.ServiceModel.Channels.Message message)
  {
    Console.WriteLine("GetInstance is called:");
    return this.service;
  }

  public object GetInstance(InstanceContext instanceContext)
  {
    Console.WriteLine("GetInstance is called:");
    return this.service;
  }

  public void ReleaseInstance(InstanceContext instanceContext, object instance)
  {
    Console.WriteLine("ReleaseInstance is called. The SingletonBehaviorAttribute never releases.");
  }

  #endregion
}
Public Class ObjectProviderBehavior
    Implements IInstanceProvider

  Private message As String
  Private service As SampleService = Nothing

  Public Sub New(ByVal msg As String)
    Console.WriteLine("The non-default constructor has been called.")
    Me.message = msg
    Me.service = New SampleService("Singleton sample service.")
  End Sub

  #Region "IInstanceProvider Members"

  Public Function GetInstance(ByVal instanceContext As InstanceContext, ByVal message As System.ServiceModel.Channels.Message) As Object Implements IInstanceProvider.GetInstance
    Console.WriteLine("GetInstance is called:")
    Return Me.service
  End Function

  Public Function GetInstance(ByVal instanceContext As InstanceContext) As Object Implements IInstanceProvider.GetInstance
    Console.WriteLine("GetInstance is called:")
    Return Me.service
  End Function

  Public Sub ReleaseInstance(ByVal instanceContext As InstanceContext, ByVal instance As Object) Implements IInstanceProvider.ReleaseInstance
    Console.WriteLine("ReleaseInstance is called. The SingletonBehaviorAttribute never releases.")
  End Sub

  #End Region
End Class

In het volgende codevoorbeeld ziet u hoe u een aangepast kenmerk implementeert dat wordt geïmplementeerd IContractBehavior om de provider van het aangepaste service-exemplaar in te voegen. Het implementeert IContractBehaviorAttributeook , waarmee het gebruik wordt gebonden aan een specifiek contract.

public class SingletonBehaviorAttribute : Attribute, IContractBehaviorAttribute, IContractBehavior
{

  #region IContractBehaviorAttribute Members

  public Type TargetContract
  {
    get { return typeof(ISampleService); }
  }

  #endregion

  #region IContractBehavior Members

  public void AddBindingParameters(ContractDescription description, ServiceEndpoint endpoint, System.ServiceModel.Channels.BindingParameterCollection parameters)
  {
    return;
  }

  public void ApplyClientBehavior(ContractDescription description, ServiceEndpoint endpoint, ClientRuntime clientRuntime)
  {
    return;
  }

  public void ApplyDispatchBehavior(ContractDescription description, ServiceEndpoint endpoint, DispatchRuntime dispatch)
  {
    dispatch.InstanceProvider = new ObjectProviderBehavior("Custom ObjectProviderBehavior constructor.");
  }

  public void Validate(ContractDescription description, ServiceEndpoint endpoint)
  {
    return;
  }

  #endregion
}
Public Class SingletonBehaviorAttribute
    Inherits Attribute
    Implements IContractBehaviorAttribute, IContractBehavior

  #Region "IContractBehaviorAttribute Members"

  Public ReadOnly Property TargetContract() As Type Implements IContractBehaviorAttribute.TargetContract
    Get
        Return GetType(ISampleService)
    End Get
  End Property

  #End Region

  #Region "IContractBehavior Members"

  Public Sub AddBindingParameters(ByVal description As ContractDescription, ByVal endpoint As ServiceEndpoint, ByVal parameters As System.ServiceModel.Channels.BindingParameterCollection) Implements IContractBehavior.AddBindingParameters
    Return
  End Sub

  Public Sub ApplyClientBehavior(ByVal description As ContractDescription, ByVal endpoint As ServiceEndpoint, ByVal clientRuntime As ClientRuntime) Implements IContractBehavior.ApplyClientBehavior
    Return
  End Sub

  Public Sub ApplyDispatchBehavior(ByVal description As ContractDescription, ByVal endpoint As ServiceEndpoint, ByVal dispatch As DispatchRuntime) Implements IContractBehavior.ApplyDispatchBehavior
    dispatch.InstanceProvider = New ObjectProviderBehavior("Custom ObjectProviderBehavior constructor.")
  End Sub

  Public Sub Validate(ByVal description As ContractDescription, ByVal endpoint As ServiceEndpoint) Implements IContractBehavior.Validate
    Return
  End Sub

  #End Region
End Class

Opmerkingen

Gebruik de GetInstance(InstanceContext, Message) methode om het exacte serviceobject te bepalen dat een WCF-service ontvangt wanneer er een nieuwe wordt gemaakt.

Van toepassing op