Returns an enumerable set that contains all the members that are exposed by this XamlType.
Assembly: System.Xaml (in System.Xaml.dll)
This method can be invoked when a caller gets a value from GetAllMembers.
Although GetAllMembers returns a generic collection, this Lookup method returns a generic enumerable set.
The default implementation uses the internal CLR reflection. For cases where UnderlyingType is null, the default implementation can use BaseType, if it is available. This behavior calls recursively to attempt to find a valid base type, and returns null if no valid base type exists.
Override this method if you are not relying on default internal CLR reflection and are using metadata or other techniques for reporting the XAML type system information or schema information of a type. A null return should be reserved for cases where information cannot be determined because of lack of type system or reflection support. If a type is valid, reflection or other techniques are available; if a type does not have members, you should instead return an empty IEnumerable<T> set.
Return values for and LookupAllAttachableMembers should be mutually exclusive. If you have a situation where a backing type system property can support a standard instance usage as well as an attachable usage, that member should be reported as two different XamlMember values, with one value appearing in the attachable list and another in the standard members list.