|Microsoft DirectX 9.0|
The IsPartiallySpecified method determines if the media type is partially defined. A media type is partial if the major type, subtype, or format type is GUID_NULL.
BOOL IsPartiallySpecified(void) const;
Returns TRUE if the media type is partially specified. Otherwise, returns FALSE.
The IPin::Connect method can accept partial media types.
The implementation does not actually test the subtype. If there is a specified format type, the media type is not considered partial, even if the subtype is GUID_NULL.