Applying Attributes to Configure COM+ Services

This topic provides the default value of each design-time attribute in the System.EnterpriseServices namespace. by knowing the default value of each attribute, you can eliminate unnecessary attributes in your code. If you are not familiar with the role of attributes on metadata, see Extending Metadata Using Attributes.

The following is the default usage information for each service-related attribute:

• Attribute scope. Identifies whether the attribute applies to only a method, class, or to an entire assembly.

• Unconfigured default value. Displays the value that COM+ assigns to the field when the attribute is omitted from code. For example, if you omit the JustInTimeActivationAttribute attribute from a class, COM+ sets the default value to False.

• Configured default value. Displays the value that COM+ assigns to a field when you apply an attribute but omit the attribute value. The following example shows how to set the JustInTimeActivationAttribute attribute to True on a class:

  Imports System.EnterpriseServices
  <JustInTimeActivation()> Public Class Account 
  Inherits ServicedComponent
     Shared Sub Main()
     End Sub
  End Class 
  [C#]
  using System.EnterpriseServices;
  [JustInTimeActivation]
  public class Account : ServicedComponent
  {
     static void Main() 
  {}
  }
  

  Makefile.bat

  You can compile the example as follows:

  vbc /t:exe /r:System.EnterpriseServices.dll Demo.vb
  [C#]
  csc /t:exe /r:System.EnterpriseServices.dll Demo.cs
  

Service-Related Attributes

The following table lists the scope and default values, configured and unconfigured, for service-related attributes.

Attribute	Attribute scope	Unconfigured default value	Configured default value
ApplicationAccessControlAttribute	Assembly	True	True
ApplicationActivationAttribute	Assembly	Library	No default
ApplicationIDAttribute	Assembly	Generated GUID	No default
ApplicationNameAttribute	Assembly	Assembly name	No default
ApplicationQueuingAttribute	Assembly	No default	No default
AutoCompleteAttribute	Method	False	True
ComponentAccessControlAttribute	Class	False	True
COMTIIntrinsicsAttribute	Class	False	True
ConstructionEnabledAttribute	Class	False	True
DescriptionAttribute	Assembly Class Method Interface	No default	No default
EventClassAttribute	Class	No default	FireInParallel = False AllowInprocSubsribers = True PublisherFilter = Null
EventTrackingEnabledAttribute	Class	False	True
ExceptionClassAttribute	Class	No default	No Default
IISIntrinsicsAttribute	Class	False	True
InterfaceQueuingAttribute	Class Interface	False	True
JustInTimeActivationAttribute	Class	False	True
LoadBalancingSupportedAttribute	Class	False	True
MustRunInClientContextAttribute	Class	False	True
ObjectPoolingAttribute	Class	False	True
PrivateComponentAttribute	Class	No default	Private
SecureMethodAttribute	Assembly Class Method	No default	No default
SecurityRoleAttribute	Assembly Class Interface	No default	No default
SynchronizationAttribute	Class	False	SynchronizationOption.Required
TransactionAttribute	Class	False	TransactionOption.Required TransactionIsolationLevel.Serializable Timeout = infinite

See Also

Writing Serviced Components | System.EnterpriseServices | Serviced Component Overview | Registering Serviced Components | Serviced Component Example | Summary of Available COM+ Services | Extending Metadata Using Attributes | System.EnterpriseServices Namespace