internal static bool IsValidDataGrid(DataGrid dgr)
        {
            bool _value = true;
            if (dgr != null)
            {
                for (int b = 0, count = dgr.Items.Count; b < count; b++)
                {
                    foreach (DataGridColumn col in dgr.Columns)
                    {
                        if (col.GetCellContent(dgr.Items[b]) != null)
                        {
                            if (Validation.GetHasError(col.GetCellContent(dgr.Items[b])))
                            {
                                _value = false;
                            }
                        }
                    }
                }
            }
            return _value;
        }