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ComDefaultInterfaceAttribute Class

.NET Framework 4

Specifies a default interface to expose to COM. This class cannot be inherited.

System.Object
  System.Attribute
    System.Runtime.InteropServices.ComDefaultInterfaceAttribute

Namespace:  System.Runtime.InteropServices
Assembly:  mscorlib (in mscorlib.dll)
C#
C++
F#
VB
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[AttributeUsageAttribute(AttributeTargets.Class, Inherited = false)]
[ComVisibleAttribute(true)]
public sealed class ComDefaultInterfaceAttribute : Attribute

The ComDefaultInterfaceAttribute type exposes the following members.

  Name Description
Public method ComDefaultInterfaceAttribute Initializes a new instance of the ComDefaultInterfaceAttribute class with the specified System.Type object as the default interface exposed to COM.
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  Name Description
Public property TypeId When implemented in a derived class, gets a unique identifier for this Attribute. (Inherited from Attribute.)
Public property Value Gets the System.Type object that specifies the default interface to expose to COM.
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  Name Description
Public method Equals Infrastructure. Returns a value that indicates whether this instance is equal to a specified object. (Inherited from Attribute.)
Protected method Finalize Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public method GetHashCode Returns the hash code for this instance. (Inherited from Attribute.)
Public method GetType Gets the Type of the current instance. (Inherited from Object.)
Public method IsDefaultAttribute When overridden in a derived class, indicates whether the value of this instance is the default value for the derived class. (Inherited from Attribute.)
Public method Match When overridden in a derived class, returns a value that indicates whether this instance equals a specified object. (Inherited from Attribute.)
Protected method MemberwiseClone Creates a shallow copy of the current Object. (Inherited from Object.)
Public method ToString Returns a string that represents the current object. (Inherited from Object.)
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  Name Description
Explicit interface implemetation Private method _Attribute.GetIDsOfNames Maps a set of names to a corresponding set of dispatch identifiers. (Inherited from Attribute.)
Explicit interface implemetation Private method _Attribute.GetTypeInfo Retrieves the type information for an object, which can be used to get the type information for an interface. (Inherited from Attribute.)
Explicit interface implemetation Private method _Attribute.GetTypeInfoCount Retrieves the number of type information interfaces that an object provides (either 0 or 1). (Inherited from Attribute.)
Explicit interface implemetation Private method _Attribute.Invoke Provides access to properties and methods exposed by an object. (Inherited from Attribute.)
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Compilers do not necessarily respect the order in which interfaces are implemented. For example, suppose you have the following code:

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interface IBase {}interface IDerived : IBase {}class MyClass : IBase, IDerived {}

The compiler emits the implemented interfaces as IDervied, IBase. The ordering of interfaces is important when using the ClassInterfaceAttribute class with [ClassInterface(ClassInterfaceType.None)] to expose an explicit interface as the default interface. Regardless of the specified ClassInterfaceType, use the ComDefaultInterfaceAttribute attribute to specify which interface should be recognized as the default.

Note that the type decorated by the ComDefaultInterfaceAttribute must actually derive from the interface specified as the default interface.

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
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