- 判读NSString
- 判读NSNumber
#define OBJ_IS_NIL(s) (s==nil || [s isKindOfClass:[NSNull class]])
#define Number_IS_VALID(s) ([s isKindOfClass:[NSValue class]])
#define OBJ_IS_NIL(s) (s==nil || [s isKindOfClass:[NSNull class]])
#define Number_IS_VALID(s) ([s isKindOfClass:[NSValue class]])