Required field in GridView C# Devexpress

private void gridView_ValidateRow(object sender, ValidateRowEventArgs e)
{
GridView gridView = sender as GridView;
//Column 지정
GridColumn gridColumn = gridView.Columns["Column name"];
//분기 조건에 사용할 Column값 지정
string value = (string)gridView.GetRowCellValue(e.RowHandle, gridColumn);
//조건
if (value is null || value == "")
{
e.Valid = false;
gridView.SetColumnError(positionCodeColumn, "Your message");
}
}