IInstanceProvider.GetInstance Metoda
Definice
Důležité
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Vrátí objekt služby.
Přetížení
GetInstance(InstanceContext) |
Vrátí objekt služby zadaný InstanceContext objekt. |
GetInstance(InstanceContext, Message) |
Vrátí objekt služby zadaný InstanceContext objekt. |
GetInstance(InstanceContext)
Vrátí objekt služby zadaný InstanceContext objekt.
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
Parametry
- instanceContext
- InstanceContext
Aktuální objekt InstanceContext.
Návraty
Objekt služby definovaný uživatelem.
Příklady
Následující příklad kódu ukazuje, jak implementovat IInstanceProvider , které poskytuje chování "singleton". Vždy vrátí stejnou instanci služby a nerecykluje ji.
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
Následující příklad kódu ukazuje, jak implementovat vlastní atribut, který implementuje IContractBehavior vložení vlastního zprostředkovatele instance služby. Implementuje také , který svázá IContractBehaviorAttributejeho použití s konkrétním kontraktem.
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
Poznámky
Použijte metodu GetInstance(InstanceContext) k řízení přesného objektu služby, který služba WCF obdrží, když se pokusí vytvořit nový.
Platí pro
GetInstance(InstanceContext, Message)
Vrátí objekt služby zadaný InstanceContext objekt.
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
Parametry
- instanceContext
- InstanceContext
Aktuální objekt InstanceContext.
- message
- Message
Zpráva, která aktivovala vytvoření objektu služby.
Návraty
Objekt služby.
Příklady
Následující příklad kódu ukazuje, jak implementovat IInstanceProvider , které poskytuje chování "singleton". Vždy vrátí stejnou instanci služby a nerecykluje ji.
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
Následující příklad kódu ukazuje, jak implementovat vlastní atribut, který implementuje IContractBehavior vložení vlastního zprostředkovatele instance služby. Implementuje také , který svázá IContractBehaviorAttributejeho použití s konkrétním kontraktem.
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
Poznámky
Použijte metodu GetInstance(InstanceContext, Message) k řízení přesného objektu služby, který služba WCF obdrží, když se pokusí vytvořit nový.