Dear all
thanks very much for the reply. I have tried to record a journal file and use that as a reference to write c++ code to covert prt file to igs. Blow is the c++ file I have tried:
//------------------
UF_initialize();
// Initialize the NX Open C++ API environment
NXOpen::Session *theSession = NXOpen::Session::GetSession();
// NXOpen:

art *Part1=(NXOpen:

art*)NXOpen::NXObjectManager::Get(part_tag);
NXOpen:

exManager *DexManager1=NULL;
*DexManager1= NXOpen:

exManager(theSession);
NXOpen::IgesCreator *igesCreator1=DexManager1->CreateIgesCreator();
igesCreator1->SetExportModelData(true);
igesCreator1->SetExportDrawings(true);
igesCreator1->SetMapTabCylToBSurf(true);
igesCreator1->SetBcurveTol(0.0508);
igesCreator1->SetIdenticalPointResolution(0.001);
igesCreator1->SetMaxThreeDMdlSpace(10000.0);
igesCreator1->SetOutputFile(obj->getname()+".igs");
igesCreator1->SetSettingsFile("/igesexport.def");
igesCreator1->SetMaxLineThickness(2.0);
igesCreator1->SetSysDefmaxThreeDMdlSpace(true);
igesCreator1->SetSysDefidenticalPointResolution(true);
igesCreator1->SetInputFile(obj->getname()+".prt");
igesCreator1->SetFileSaveFlag(true);
NXOpen::NXObject *nxObject1= igesCreator1->Commit();
igesCreator1->Destroy();
UF_terminate();
//----------------------------
but it gives me error at the place of :
*DexManager1= NXOpen:

exManager(theSession);
NXOpen::IgesCreator *igesCreator1=DexManager1->CreateIgesCreator();
could anyone please tell me how to correct it? How can I initialize the CreateIgesCreator() method from a nxsession?
thanks