void HandleCellValidating(object sender, DataGridViewCellValidatingEventArgs e)
{
var gridViewCell = FDataGridView[e.ColumnIndex, e.RowIndex];
var cell = gridViewCell.Tag as ICell;
var value = Convert.ChangeType(gridViewCell.FormattedValue, cell.ValueType);
if (!cell.ReadOnly)
{
if (!cell.AcceptsValue(value))
{
FDataGridView.CancelEdit();
}
}
}
