FaultException Class

In a service, use the FaultException class to create an untyped fault to return to the client for debugging purposes.

In a client, catch FaultException objects to handle unknown or generic faults, such as those returned by a service with the IncludeExceptionDetailInFaults property set to true. Because FaultException extends CommunicationException, remember to catch any FaultException objects prior to catching CommunicationException objects if you want to catch them separately.

Note
Duplex services can also catch FaultException objects returned from their interaction with a duplex client.

In general, it is strongly recommended that you use the FaultContractAttribute to design your services to return strongly-typed SOAP faults (and not managed exception objects) for all fault cases in which you decide the client requires fault information. However, use the FaultException in the following situations:

• To send SOAP faults from a service for debugging purposes.

• To catch SOAP faults on a client when the faults are not part of the service contract.

Throw FaultException objects when you want the string to be passed to the constructor and retrieved by the client by calling the FaultException<TDetail>.ToString method. If you specify a fault contract of type System.ServiceModel.FaultException<TDetail> where the type parameter is System.String, the string value is available as the FaultException<TDetail>.Detail property and not by calling FaultException<TDetail>.ToString.

For details, see Handling Faults in Windows Communication Foundation Contracts.

The following code example shows the use of a try/catch block to catch and handle FaultException objects thrown from a service. This often occurs when debugging is turned on in the service application.

<system.serviceModel>
  <behaviors>
    <serviceBehaviors>
      <behavior>
        <serviceMetadata httpGetEnabled="true"/>
        <serviceDebug includeExceptionDetailInFaults="false"/>
        <!-- Add the greetingFaultBehavior -->
        <greetingFaultBehavior />
      </behavior>
    </serviceBehaviors>
  </behaviors>
  <serviceHostingEnvironment multipleSiteBindingsEnabled="true" />
  <!-- Register the class that implements the configuration element -->
  <extensions>
    <behaviorExtensions>
      <add
        name="greetingFaultBehavior"
        type="GreetingService.GreetingFaultBehaviorExtensionElement, GreetingService, Version=1.0.0.0, Culture=neutral"
      />
    </behaviorExtensions>
  </extensions>
</system.serviceModel>

.NET Framework

.NET Framework Client Profile

Portable Class Library

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

Reference