entity A has a entity B property
entity B has a entity C property
entity X has a entity Z property

when SerializationMode is Complex,the serialize result of entity A is very big

in a part,i need serialize A, A.B, A.B.C
in another part,I need serialize A, A.B only
it means a property need serialize or not is not same always
so,set SerializeIgnoreAttribute for entity properties is not applicable

i think, serialize or not, depends on the given Fields of Reader