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Can you explain me what is the purpose of the CExtGridDataProvider and CExtGridDataProviderMemory class, their basic use, and the basic functions to call in order to get them useful?

Thanks, Paolo

The CExtGridDataProvider class is an abstract class which defines the standard data provider API for a windowless component. Generally the data provider is an object which manages the two dimensional array of the grid cells and provides the CExtGridWnd window with a range of displayed CExtGridCell cells including inner data cells and outer header cells. The CExtGridDataProviderMemory class is fully featured implementation of the data provider which keeps all the cells in the internal memory heap. This class is used by default in the grid window. The memory data provider is demonstrated in all the grid windows of the SimpleGrids sample. The CExtGridDataProviderRecordSet class is an abstract data provider class which is convenient for implementing a cacheable data provider based on a data-base query result with a known number of columns and a known or an unknown number of rows. The recordset data provider is demonstrated in the AdoRecordSetView sample application.

In most of cases you don’t need to work with data providers directly. We can discuss any details of your task(s) and advise you whether coding any kind of custom data provider is needed.