C# ASP.NET I can't set color on my Gridview when cell is empty

Question

I need to change color if string is empty it set to red color

foreach (TableCell cell in e.Row.Cells)
{
     if (cell.Equals(" ")||cell.Equals(string.Empty)||string.IsNullOrWhiteSpace(cell.ToString()))//if (cell.ToString() == " ")
     {
          cell.BackColor = Color.Red;
     }
     else
     {
          cell.BackColor = Color.White;
     }            
}

[ ]

Answer 1

foreach (TableCell cell in e.Row.Cells)
{
    if (e.Row.RowType == DataControlRowType.DataRow)
    {
        string text = cell.Text.Trim();
        cell.BackColor = (String.IsNullOrEmpty(text) || text == " ") ? Color.Red : Color.White;
    }
}