CException difference in VS2005
in [MFC]
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From: Eric Margheim on 13 Jun 2006 14:03 I am getting a compiler error on the following bit of code catch (CException e) This code compiled fine in VS6. The VS2005 compiler says the following and points to the following code in afx.h error C2259: 'CException' : cannot instantiate abstract class 1> due to following members: 1> 'CException::~CException(void)' : is abstract virtual ~CException() = 0; Any thought on what I need to change here? Thanks
From: Doug Harrison [MVP] on 13 Jun 2006 15:30 On Tue, 13 Jun 2006 13:03:41 -0500, "Eric Margheim" <NOSPAM***eric(a)prism-grp.com***NOSPAM> wrote: >I am getting a compiler error on the following bit of code > >catch (CException e) > >This code compiled fine in VS6. The VS2005 compiler says the following and >points to the following code in afx.h > >error C2259: 'CException' : cannot instantiate abstract class >1> due to following members: >1> 'CException::~CException(void)' : is abstract > >virtual ~CException() = 0; > > > >Any thought on what I need to change here? You need to change this to: catch (CException* e) { // Use e... e->Delete(); // Do this if you don't rethrow } It may have compiled OK in VC6, but it never worked right, because MFC only ever throws pointers to exceptions. So your code was never capable of catching MFC exceptions thrown in the normal, correct way (well, normal and correct for MFC, anyway). -- Doug Harrison Visual C++ MVP
From: Eric Margheim on 13 Jun 2006 15:37 Cool thanks. "Doug Harrison [MVP]" <dsh(a)mvps.org> wrote in message news:ee4u82linn70t3uu5uehavn74ebo0fa4ok(a)4ax.com... > On Tue, 13 Jun 2006 13:03:41 -0500, "Eric Margheim" > <NOSPAM***eric(a)prism-grp.com***NOSPAM> wrote: > >>I am getting a compiler error on the following bit of code >> >>catch (CException e) >> >>This code compiled fine in VS6. The VS2005 compiler says the following >>and >>points to the following code in afx.h >> >>error C2259: 'CException' : cannot instantiate abstract class >>1> due to following members: >>1> 'CException::~CException(void)' : is abstract >> >>virtual ~CException() = 0; >> >> >> >>Any thought on what I need to change here? > > You need to change this to: > > catch (CException* e) > { > // Use e... > e->Delete(); // Do this if you don't rethrow > } > > It may have compiled OK in VC6, but it never worked right, because MFC > only > ever throws pointers to exceptions. So your code was never capable of > catching MFC exceptions thrown in the normal, correct way (well, normal > and > correct for MFC, anyway). > > -- > Doug Harrison > Visual C++ MVP
From: Eric Margheim on 13 Jun 2006 16:10 >>virtual ~CException() = 0; >> >> >> >>Any thought on what I need to change here? > > You need to change this to: > > catch (CException* e) > { > // Use e... > e->Delete(); // Do this if you don't rethrow > } > > It may have compiled OK in VC6, but it never worked right, because MFC > only > ever throws pointers to exceptions. So your code was never capable of > catching MFC exceptions thrown in the normal, correct way (well, normal > and > correct for MFC, anyway). > This is bad code too evidentally. throw new CException(TRUE);
From: Doug Harrison [MVP] on 13 Jun 2006 16:24
On Tue, 13 Jun 2006 15:10:26 -0500, "Eric Margheim" <NOSPAM***eric(a)prism-grp.com***NOSPAM> wrote: >This is bad code too evidentally. > >throw new CException(TRUE); Since the class is now abstract, yes. -- Doug Harrison Visual C++ MVP |