public static void FormatColumnHeader(BandedGridColumn gc)
        {
            switch (gc.UnboundType)
            {
            case DevExpress.Data.UnboundColumnType.Decimal: SetFormat(gc, "#,###.##"); break;

            case DevExpress.Data.UnboundColumnType.DateTime: SetFormat(gc, "dd/MM/yyyy"); break;
            }
        }
 /// <summary>
 /// Thiết lập Format
 /// </summary>
 /// <param name="gc"></param>
 /// <param name="format"></param>
 protected static void SetFormat(BandedGridColumn gc, string format)
 {
     gc.DisplayFormat.FormatString = format;
     gc.DisplayFormat.FormatType   = DevExpress.Utils.FormatType.Custom;
 }