ComDefaultInterfaceAttribute Class

Definition

Namespace:

System.Runtime.InteropServices

Assembly:

System.Runtime.InteropServices.dll

Source:

ComDefaultInterfaceAttribute.cs

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

public ref class ComDefaultInterfaceAttribute sealed : Attribute

[System.AttributeUsage(System.AttributeTargets.Class, Inherited=false)]
public sealed class ComDefaultInterfaceAttribute : Attribute

[<System.AttributeUsage(System.AttributeTargets.Class, Inherited=false)>]
type ComDefaultInterfaceAttribute = class
    inherit Attribute

Public NotInheritable Class ComDefaultInterfaceAttribute
Inherits Attribute

Inheritance

Object

Attribute

ComDefaultInterfaceAttribute

Attributes

AttributeUsageAttribute

Remarks

Compilers do not necessarily respect the order in which interfaces are implemented. For example, suppose you have the following code:

interface IBase {}

interface IDerived : IBase {}

class MyClass : IBase, IDerived {}  

The compiler emits the implemented interfaces as IDerived, 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.

Constructors

ComDefaultInterfaceAttribute(Type)

Initializes a new instance of the ComDefaultInterfaceAttribute class with the specified Type object as the default interface exposed to COM.

Properties

TypeId	When implemented in a derived class, gets a unique identifier for this Attribute. (Inherited from Attribute)
Value	Gets the Type object that specifies the default interface to expose to COM.

Methods

Equals(Object)	Returns a value that indicates whether this instance is equal to a specified object. (Inherited from Attribute)
GetHashCode()	Returns the hash code for this instance. (Inherited from Attribute)
GetType()	Gets the Type of the current instance. (Inherited from Object)
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)
Match(Object)	When overridden in a derived class, returns a value that indicates whether this instance equals a specified object. (Inherited from Attribute)
MemberwiseClone()	Creates a shallow copy of the current Object. (Inherited from Object)
ToString()	Returns a string that represents the current object. (Inherited from Object)