1) If you set the style.CellValueType for the column to typeof(DataTime), then you set style.Format for the column to specify. If this is a GridControl, you set the style for the column using the grid.ColStyles collection. If this is a GridDataBoundGrid, you set the column style using either grid.GridBoundColumn[col].StyleInfo or grid.Binder.InternalColumns[col].StyleInfo depending upon whether you have esplicitly added GridBoundColumns or not.
2) You can handle the QueryCellFormattedText event and specify the display value there.
private void gridControl1_QueryCellFormattedText(object sender, GridCellTextEventArgs e)
{
if(e.Style.CellValueType == typeof(DateTime)&& e.Style.Text.Length == 0)
{
e.Text = "00/00/0000";
e.Handled = true;
}
}
