IDataObjectImpl Class
This class provides methods for supporting Uniform Data Transfer and managing connections.
Important
This class and its members cannot be used in applications that execute in the Windows Runtime.
template<class T>
class IDataObjectImpl
T
Your class, derived from IDataObjectImpl.
| Name | Description |
|---|---|
| IDataObjectImpl::DAdvise | Establishes a connection between the data object and an advise sink. This enables the advise sink to receive notifications of changes in the object. |
| IDataObjectImpl::DUnadvise | Terminates a connection previously established through DAdvise. |
| IDataObjectImpl::EnumDAdvise | Creates an enumerator to iterate through the current advisory connections. |
| IDataObjectImpl::EnumFormatEtc | Creates an enumerator to iterate through the FORMATETC structures supported by the data object. The ATL implementation returns E_NOTIMPL. |
| IDataObjectImpl::FireDataChange | Sends a change notification back to each advise sink. |
| IDataObjectImpl::GetCanonicalFormatEtc | Retrieves a logically equivalent FORMATETC structure to one that is more complex. The ATL implementation returns E_NOTIMPL. |
| IDataObjectImpl::GetData | Transfers data from the data object to the client. The data is described in a FORMATETC structure and is transferred through a STGMEDIUM structure. |
| IDataObjectImpl::GetDataHere | Similar to GetData, except the client must allocate the STGMEDIUM structure. The ATL implementation returns E_NOTIMPL. |
| IDataObjectImpl::QueryGetData | Determines whether the data object supports a particular FORMATETC structure for transferring data. The ATL implementation returns E_NOTIMPL. |
| IDataObjectImpl::SetData | Transfers data from the client to the data object. The ATL implementation returns E_NOTIMPL. |
The IDataObject interface provides methods to support Uniform Data Transfer. IDataObject uses the standard format structures FORMATETC and STGMEDIUM to retrieve and store data.
IDataObject also manages connections to advise sinks to handle data change notifications. In order for the client to receive data change notifications from the data object, the client must implement the IAdviseSink interface on an object called an advise sink. When the client then calls IDataObject::DAdvise, a connection is established between the data object and the advise sink.
Class IDataObjectImpl provides a default implementation of IDataObject and implements IUnknown by sending information to the dump device in debug builds.
Related Articles ATL Tutorial, Creating an ATL Project
IDataObject
IDataObjectImpl
Header: atlctl.h
Establishes a connection between the data object and an advise sink.
HRESULT DAdvise(
FORMATETC* pformatetc,
DWORD advf,
IAdviseSink* pAdvSink,
DWORD* pdwConnection);
This enables the advise sink to receive notifications of changes in the object.
To terminate the connection, call DUnadvise.
See IDataObject::DAdvise in the Windows SDK.
Terminates a connection previously established through DAdvise.
HRESULT DUnadvise(DWORD dwConnection);
See IDataObject::DUnadvise in the Windows SDK.
Creates an enumerator to iterate through the current advisory connections.
HRESULT DAdvise(
FORMATETC* pformatetc,
DWORD advf,
IAdviseSink* pAdvSink,
DWORD* pdwConnection);
See IDataObject::EnumDAdvise in the Windows SDK.
Creates an enumerator to iterate through the FORMATETC structures supported by the data object.
HRESULT EnumFormatEtc(
DWORD dwDirection,
IEnumFORMATETC** ppenumFormatEtc);
See IDataObject::EnumFormatEtc in the Windows SDK.
Returns E_NOTIMPL.
Sends a change notification back to each advise sink that is currently being managed.
HRESULT FireDataChange();
A standard HRESULT value.
Retrieves a logically equivalent FORMATETC structure to one that is more complex.
HRESULT GetCanonicalFormatEtc(FORMATETC* pformatetcIn, FORMATETC* pformatetcOut);
Returns E_NOTIMPL.
See IDataObject::GetCanonicalFormatEtc in the Windows SDK.
Transfers data from the data object to the client.
HRESULT GetData(
FORMATETC* pformatetcIn,
STGMEDIUM* pmedium);
The pformatetcIn parameter must specify a storage medium type of TYMED_MFPICT.
See IDataObject::GetData in the Windows SDK.
Similar to GetData, except the client must allocate the STGMEDIUM structure.
HRESULT GetDataHere(
FORMATETC* pformatetc,
STGMEDIUM* pmedium);
Returns E_NOTIMPL.
See IDataObject::GetDataHere in the Windows SDK.
Determines whether the data object supports a particular FORMATETC structure for transferring data.
HRESULT QueryGetData(FORMATETC* pformatetc);
Returns E_NOTIMPL.
See IDataObject::QueryGetData in the Windows SDK.
Transfers data from the client to the data object.
HRESULT SetData(
FORMATETC* pformatetc,
STGMEDIUM* pmedium,
BOOL fRelease);
Returns E_NOTIMPL.
See IDataObject::SetData in the Windows SDK.