XamlMember::IsUnknown Property
Gets a value that indicates whether the member is not resolvable by the backing system that is used for type and member resolution.
Assembly: System.Xaml (in System.Xaml.dll)
Property Value
Type: System::Booleantrue if the member is not resolvable; false if the member is resolvable.
A XamlMember that is constructed with the XamlMember(String^, XamlType^, Boolean) signature returns true for IsUnknown.
For a load path that involves XamlObjectWriter, a XamlMember with true for IsUnknown cannot be written into an object graph. Under the default implementations in .NET Framework XAML Services APIs, the XamlObjectWriter::WriteStartMember call throws a XamlObjectWriterException when the relevant XamlMember reports true for IsUnknown.
You should not construct a XamlMember that has a value of true for IsUnknown unless your implementation can handle the exceptions from XamlObjectWriter, or you have other ways to adjust the XamlObjectWriter behavior.
Calling IsUnknown invokes LookupIsUnknown or a specific override of that method.
Available since 4.0