CAD中用户选择实体

CString CPaintBar::GetEncyrptCode()
{
    CString sNull = _T("");
    //选择单文本或者多文本
    ads_name ent;
    ads_point pt;
    int nRs = acedEntSel(_T("\n请选择加入的内容："), ent, pt);
    if (RTNORM != nRs)
    {
        AfxMessageBox(_T("获取失败！"));
        acedSSFree(ent);
        return sNull;
    }

    //获得所选实体Id
    AcDbObjectId entId;
    Acad::ErrorStatus es = acdbGetObjectId(entId, ent);
    if (Acad::eOk != es)
    {
        AfxMessageBox(_T("获取id失败！"));
        acedSSFree(ent);
        return sNull;
    }
    acedSSFree(ent);

    //判断所选实体是否是单文本或者多文本
    AcDbEntity *pEnt = NULL;
    es = acdbOpenObject(pEnt, entId, AcDb::kForRead);
    if (Acad::eOk != es)
    {
        AfxMessageBox(_T("获取实体失败！"));
        return sNull;
    }
    CString str;
    if (pEnt->isKindOf(AcDbText::desc()))
    {
        AcDbText *pText = NULL;
        pText = AcDbText::cast(pEnt);
        str = pText->textString();
        pText->close();
    }
    else if (pEnt->isKindOf(AcDbMText::desc()))
    {
        AcDbMText *pmText = NULL;
        pmText = AcDbMText::cast(pEnt);
        str = pmText->contents();
        pmText->close();
    }
    else
    {
        AfxMessageBox(_T("获取实体不是文本类型！"));
        pEnt->close();
        return sNull;
    }
    pEnt->close();
    return str;
}