ArrayList al = new ArrayList();

        DataTable dt = new DataTable();

        dt.Columns.Add("A",typeof(double));

        dt.Columns.Add("B", typeof(double));

        dt.Columns.Add("C", typeof(double));

        DataRow dr1 = dt.NewRow();

        dr1["A"] = 5.5;

        dr1["B"] = -20.6;

        dr1["C"] = -3.8;

        dt.Rows.Add(dr1);

        for (int i = ;i< dt.Rows.Count;i++)

        {

            al.Add(Convert.ToDouble( dt.Rows[i]["A"]));

            al.Add(Convert.ToDouble(dt.Rows[i]["B"]));

            al.Add(Convert.ToDouble(dt.Rows[i]["C"]));

        }

        al.Sort();

        Response.Write(al[al.Count - ].ToString()+"<br/>");//最大值

        Response.Write(al[].ToString());//最小值