ARX 实体的表达方式

ytcadtools

实体表达方式:handle, ObjectID,ads_name,指针point
/ h& y3 S3 ~. E  M9 C4 T; j8 aObject Arx中,表达实体的方式主要有handle, ObjectID,ads_name,指针point;这些方式之间有什么区别呢?
6 M1 u4 [9 j" t  |2 V5 ?Handle:  永远不变,存在DWG文件中;
ObjectId:每次打开一个图,所有的对象都分得一个ObjectId,这个ObjectId维持不变,直到DWG被关闭
Point: 每次得到它,它总在变,就算它代表的实体是不变的.
ads_name 同 Point一样
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( a5 a( e2 Y( L3 _) v' b以下函数是常用的:
Acad::ErrorStatus
; }3 n: }6 N, o; H: P9 kAcDbDatabase::acdbOpenObject(AcDbObject*& obj, AcDbObjectId id, AcDb::OpenMode mode,
                    Adesk::Boolean openErasedObject = Adesk::kFalse)
Acad::ErrorStatus
getAcDbObjectId(AcDbObjectId& retId,Adesk::Boolean createIfNotFound,
! I  h: E. K+ B, \; b           const AcDbHandle& objHandle,Adesk::UInt32 xRefId=0);
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AcDbObject* pObject;
AcDbHandle handle;
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pObject->getAcDbHandle(handle);
acdbGetAdsName(ads_name& objName,AcDbObjectId objId);
$ c, P  z" J% V9 c' c1 uacdbGetObjectId(AcDbObjectId& objId,ads_name objName);
acdbHandEnt(const char * handle,ads_name entres);