如何监控删除实体的操作？

hbird

想法是：
       监视每一个删除操作，通过被删除的objectId获取被删实体的属性，再根据属性判断是否有不应被删除的实体在内，执行其它操作

hdr_37210427

派生一个类

// DbReactor.cpp: implementation of the CDbReactor class.
//
//////////////////////////////////////////////////////////////////////

#include "stdafx.h"
#include "resource.h"
#include "DbReactor.h"

#ifdef _DEBUG
#undef THIS_FILE
static char THIS_FILE[]=__FILE__;
#define new DEBUG_NEW
#endif

//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////

CDbReactor::CDbReactor()
{

}

CDbReactor::~CDbReactor()
{

}

void CDbReactor::objectAppended(const AcDbDatabase *db,const AcDbObject *pObj)
{
  ads_alert("APPEND");
}

void CDbReactor::objectModified(const AcDbDatabase *db,const AcDbObject *pObj)
{
  ads_alert("MODIFY");
}

void CDbReactor::objectErased(const AcDbDatabase *db,const AcDbObject *pObj,Adesk::Boolean pErased)
{
  if(pErased) ads_alert("DELETE");
}

// DbReactor.h: interface for the CDbReactor class.
//
//////////////////////////////////////////////////////////////////////

#if !defined(AFX_DBREACTOR_H__ED11D52E_E8ED_43A0_90CE_8BB65D78A51A__INCLUDED_)
#define AFX_DBREACTOR_H__ED11D52E_E8ED_43A0_90CE_8BB65D78A51A__INCLUDED_

#if _MSC_VER > 1000
#pragma once
#endif // _MSC_VER > 1000

class CDbReactor : public AcDbDatabaseReactor 
{
public:
 CDbReactor();
 virtual ~CDbReactor();

  void objectAppended(const AcDbDatabase *db,const AcDbObject *pObj);
  void objectModified(const AcDbDatabase *db,const AcDbObject *pObj);
  void objectErased(const AcDbDatabase *db,const AcDbObject *pObj,Adesk::Boolean pErased);

};

#endif // !defined(AFX_DBREACTOR_H__ED11D52E_E8ED_43A0_90CE_8BB65D78A51A__INCLUDED_)

增加监控函数

void WatchDb()
{
  if(gpDbr==NULL) gpDbr = new CDbReactor();

  AcDbDatabase *pCur=acdbHostApplicationServices()->workingDatabase();
  pCur->addReactor(gpDbr);
}

//清除监控函数

void ClearReactors()
{
  AcDbDatabase *pCur=acdbHostApplicationServices()->workingDatabase();

  if(pCur!=NULL) pCur->removeReactor(gpDbr);
  delete gpDbr;
  gpDbr=NULL;
}

在初始化时增加监控

void InitApplication()
{
  // TODO: add your initialization functions

  WatchDb();

}

// Unload this application. Unregister all objects
// registered in InitApplication.

//在退出时清除监控
void UnloadApplication()
{
 // NOTE: DO NOT edit the following lines.
 //{{AFX_ARX_EXIT
 //}}AFX_ARX_EXIT

  ClearReactors();

  //deleteAcRxClass(CPersistentReactor::desc());
 // TODO: clean up your application
}