DefaultInterfaceAttribute Class
[ This article is for Windows Phone 8 developers. If you’re developing for Windows 10, see the latest documentation. ]
Specifies the default interface of a managed Windows Runtime class.
System::Attribute
System.Runtime.InteropServices.WindowsRuntime::DefaultInterfaceAttribute
Assembly: mscorlib (in mscorlib.dll)
The DefaultInterfaceAttribute type exposes the following members.
| Name | Description | |
|---|---|---|
 | DefaultInterfaceAttribute | Initializes a new instance of the DefaultInterfaceAttribute class. |
| Name | Description | |
|---|---|---|
| Equals | Infrastructure. Returns a value that indicates whether this instance is equal to a specified object. (Inherited from Attribute.) |
 | Finalize | Allows an object to try to free resources and perform other cleanup operations before the Object is reclaimed by garbage collection. (Inherited from Object.) |
| GetHashCode | Returns the hash code for this instance. (Inherited from Attribute.) |
| GetType | Gets the Type of the current instance. (Inherited from Object.) |
| Match | 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.) |
When you develop Windows Runtime Components, use this attribute when you want to specify the default interface that is used to marshal the class the attribute is applied to. This is not necessary if you allow the class interfaces to be generated automatically.
A Windows Runtime class must have a default interface. If the WinMdExp.exe utility does not detect a default interface for a class when it builds your Windows Runtime component, it chooses an interface as follows:
If the class has automatically generated interfaces, it uses the first one as the default.
If the class doesn't have any automatically generated interfaces, it uses the first interface in the class's interface implementation list.
You can apply the DefaultInterfaceAttribute attribute to the class, or apply the Windows.Foundations.Metadata.DefaultAttribute attribute to an interface. The latter takes precedence if both attributes are supplied.