error converting datatype

Question

 Good morning

 I have this 2 lines to get the date time 

 txtdate.Text= DateTime.Now.Date.ToString();
 string  dt = Convert.ToDateTime(txtdate.Text).ToString();

and i pass it  to the stored procedure as parameter as  following :

cmd.Parameters.AddWithValue("@Reg_Date", dt); 

when it reach the cmd.ExecuteNonQuery();

it will stop and give the error :
Error converting data type nvarchar to datetime
thanks in advance