Class: TEgDBGridEx
property OnCheckChange: TEgDBGridCheckChangeEvent;Fired just before a checkbox cell’s boolean field value is toggled,
whether by a mouse click on the checkbox glyph or by pressing Space with
the cell selected. Column identifies the cell about to
change. Fires before the dataset is put in edit state and before the
field value is actually flipped, so a handler can inspect the current
value, or veto the change indirectly by raising an exception. Also
available at column level (see TEgColumn.OnCheckChange);
when both are assigned, the grid-level handler runs first. See TEgDBGridCheckChangeEvent.