I need to check all the records in a table.I'm having a foreach loop in my web application. I need to use this loop in crystal report's formula field. I'm new to crystal reports and I have no idea with how to write it in formula field. Can anyone help me?

     

foreach (DataRow dr in ds.Tables[0].Rows)
        {
            type = (dr["type"]).ToString();
            if (type == "c")
            {
                c_total = c_total + Convert.ToDouble(dr["amount"]);
            }
            else if (type == "d")
            {
                d_total = d_total + Convert.ToDouble(dr["amount"]);
            }
        }