COleDBRecordView Class

A view that displays database records in controls.

Syntax

class COleDBRecordView : public CFormView

Members

Protected Constructors

Name	Description
COleDBRecordView::COleDBRecordView	Constructs a COleDBRecordView object.

Public Methods

Name	Description
COleDBRecordView::OnGetRowset	Returns a standard HRESULT value.
COleDBRecordView::OnMove	Updates the current record (if dirty) on the data source and then moves to the specified record (next, previous, first, or last).

Remarks

The view is a form view directly connected to a CRowset object. The view is created from a dialog template resource and displays the fields of the CRowset object in the dialog template's controls. The COleDBRecordView object uses dialog data exchange (DDX), and the navigational functionality built into CRowset, to automate the movement of data between the controls on the form and the fields of the rowset. COleDBRecordView also supplies a default implementation for moving to the first, next, previous, or last record and an interface for updating the record currently on view.

You can use DDX functions with COleDbRecordView to get data directly from the database recordset and display it in a dialog control. You should use the DDX_* methods (such as DDX_Text), not the DDX_Field* functions (such as DDX_FieldText) with COleDbRecordView. DDX_FieldText will not work with COleDbRecordView because DDX_FieldText takes an additional argument of type CRecordset* (for CRecordView) or CDaoRecordset* (for CDaoRecordView).

Note

If you are working with the Data Access Objects (DAO) classes rather than the OLE DB Consumer Template classes, use class CDaoRecordView instead. For more information, see the article Overview: Database Programming.

COleDBRecordView keeps track of the user's position in the rowset so that the record view can update the user interface. When the user moves to either end of the rowset, the record view disables user interface objects — such as menu items or toolbar buttons — for moving further in the same direction.

For more information about rowset classes, see the Using OLE DB Consumer Templates article.

Inheritance Hierarchy

CObject

CCmdTarget

CWnd

CView

CScrollView

CFormView

COleDBRecordView

Requirements

Header: afxoledb.h

COleDBRecordView::COleDBRecordView

Constructs a COleDBRecordView object.

COleDBRecordView(LPCTSTR lpszTemplateName);
COleDBRecordView(UINT nIDTemplate);

Parameters

lpszTemplateName
Contains a null-terminated string that is the name of a dialog-template resource.

nIDTemplate
Contains the ID number of a dialog-template resource.

Remarks

When you create an object of a type derived from COleDBRecordView, invoke one of the constructors to create the view object and identify the dialog resource on which the view is based. You can identify the resource either by name (pass a string as the argument to the constructor) or by its ID (pass an unsigned integer as the argument).

Note

Your derived class must supply its own constructor. In the constructor, invoke the constructor, COleDBRecordView::COleDBRecordView, with the resource name or ID as an argument.

COleDBRecordView::OnGetRowset

Returns a handle for the CRowset<> object associated with the record view.

virtual CRowset<>* OnGetRowset() = 0;

Return Value

A standard HRESULT value.

Remarks

You must override this member function to construct or obtain a rowset object and return a handle to it. If you declare your record view class with ClassWizard, the wizard writes a default override for you. ClassWizard's default implementation returns the rowset handle stored in the record view if one exists. If not, it constructs a rowset object of the type you specified with ClassWizard and calls its Open member function to open the table or run the query, and then returns a handle to the object.

Note

Previous to MFC 7.0, OnGetRowset returned a pointer to CRowset. If you have code that calls OnGetRowset, you need to change the return type to the templatized class CRowset<>.

Example

CFrameWnd* pFrame = (CFrameWnd*)AfxGetMainWnd();
COleDBRecordView* pView = (COleDBRecordView*)pFrame->GetActiveView();

// CProductAccessor is a user-defined accessor class
CRowset<CAccessor<CProductAccessor>>* pRowSet =
(CRowset<CAccessor<CProductAccessor>>*)pView->OnGetRowset();

For more information and examples, see the article Record Views: Using a Record View.

COleDBRecordView::OnMove

Moves to a different record in the rowset and display its fields in the controls of the record view.

virtual BOOL OnMove(UINT nIDMoveCommand);

Parameters

nIDMoveCommand
One of the following standard command ID values:

• ID_RECORD_FIRST — Move to the first record in the recordset.

• ID_RECORD_LAST — Move to the last record in the recordset.

• ID_RECORD_NEXT — Move to the next record in the recordset.

• ID_RECORD_PREV — Move to the previous record in the recordset.

Return Value

Nonzero if the move was successful; otherwise 0 if the move request was denied.

Remarks

The default implementation calls the appropriate Move member function of the CRowset object associated with the record view.

By default, OnMove updates the current record on the data source if the user has changed it in the record view.

The Application Wizard creates a menu resource with First Record, Last Record, Next Record, and Previous Record menu items. If you select the Dockable Toolbar option, The Application Wizard also creates a toolbar with buttons corresponding to these commands.

If you move past the last record in the recordset, the record view continues to display the last record. If you move backward past the first record, the record view continues to display the first record.

See also

Hierarchy Chart