Check the system date using c# asp.net

i need to fill color in my grid if the date today or the date is expired
if date today the color will be yellow and expiry date is red. here's my code
if (e.Row.Cells[8].Text == DateTime.Now.ToString("DD/MM/YYYY"))
{ e.Row.Cells[8].BackColor = System.Drawing.Color.Yellow; }
for exp.?? need help please