The MFn::Type enumeration is used throughout the API to indicate item types.
MObject class has an apiType() method which you can use to determine the type of object the MObject is referencing. Each function set also has a type() method which can be used to determine the function set type.MGlobal::getFunctionSetList() also returns an array of strings representing the types of function sets that will accept an object.See also Objects and Function Sets.