Procedura: controllare l'istanza del servizio

  • Articolo

L'impostazione della modalità di istanza di un servizio consente di specificare quando vengono creati una classe System.ServiceModel.InstanceContext e il relativo oggetto servizio definito dall'utente associato. Per un elenco delle modalità possibili, vedere l'enumerazione InstanceContextMode. Per altre informazioni sui comportamenti, vedere Configurazione ed estensione del runtime con i comportamenti. Per alcuni esempi funzionanti, vedere Comportamenti.

Per controllare la durata dell'istanza del servizio tramite codice

  1. Applicare la classe ServiceBehaviorAttribute alla classe di servizi.

  2. Impostare la proprietà InstanceContextMode su uno dei valori seguenti: PerCall, PerSession o Single.

    [ServiceBehaviorAttribute(InstanceContextMode = InstanceContextMode.PerCall)]

    <ServiceBehaviorAttribute(InstanceContextMode:=InstanceContextMode.PerCall)> _
Public Class CalculatorService

Esempio

Nell'esempio di codice seguente, la proprietà InstanceContextMode dell'attributo ServiceBehaviorAttribute viene impostata su PerCall.

// Define a service contract.
[ServiceContract(Namespace = "http://Microsoft.ServiceModel.Samples")]
public interface ICalculator
{
    [OperationContract]
    double Add(double n1, double n2);
    [OperationContract]
    double Subtract(double n1, double n2);
    [OperationContract]
    double Multiply(double n1, double n2);
    [OperationContract]
    double Divide(double n1, double n2);
}

// Service class which implements the service contract.
[ServiceBehaviorAttribute(InstanceContextMode = InstanceContextMode.PerCall)]
public class CalculatorService : ICalculator
{
    public double Add(double n1, double n2)
    {
        return n1 + n2;
    }

    public double Subtract(double n1, double n2)
    {
        return n1 - n2;
    }

    public double Multiply(double n1, double n2)
    {
        return n1 * n2;
    }

    public double Divide(double n1, double n2)
    {
        return n1 / n2;
    }
}

' Define a service contract.
<ServiceContract([Namespace]:="http://Microsoft.ServiceModel.Samples")> _
Public Interface ICalculator
    <OperationContract()> _
    Function Add(ByVal n1 As Double, ByVal n2 As Double) As Double
    <OperationContract()> _
    Function Subtract(ByVal n1 As Double, ByVal n2 As Double) As Double
    <OperationContract()> _
    Function Multiply(ByVal n1 As Double, ByVal n2 As Double) As Double
    <OperationContract()> _
    Function Divide(ByVal n1 As Double, ByVal n2 As Double) As Double
End Interface

' Service class which implements the service contract.
<ServiceBehaviorAttribute(InstanceContextMode:=InstanceContextMode.PerCall)> _
Public Class CalculatorService
    Implements ICalculator

    Public Function Add(ByVal n1 As Double, ByVal n2 As Double) As Double _
    Implements ICalculator.Add
        Return n1 + n2

    End Function


    Public Function Subtract(ByVal n1 As Double, ByVal n2 As Double) As Double _
    Implements ICalculator.Subtract
        Return n1 - n2
    End Function

    Public Function Multiply(ByVal n1 As Double, ByVal n2 As Double) As Double _
    Implements ICalculator.Multiply
        Return n1 * n2
    End Function

    Public Function Divide(ByVal n1 As Double, ByVal n2 As Double) As Double _
    Implements ICalculator.Divide
        Return n1 / n2
    End Function
End Class

Vedi anche