static void Main(string[] args)
{
        DataTable dt = InitialData();

        //查找 DataTable 中 A列 值 大于中 A_3 的列
        DataRow[] drs = dt.Select("A > 'A_3'", "A desc");

        Console.WriteLine("A\tB\tC\tD");

        //遍历数据
        foreach (DataRow row in drs)
        {
                string a = row["A"] as string;
                string b = row["B"] as string;
                string c = row["C"] as string;
                string d = row["D"] as string;
                Console.WriteLine(a + "\t" + b + "\t" + c + "\t" + d);
        }

        Console.ReadKey();
}

///

/// 初始化测试数据
///

public static DataTable InitialData()
{
        //创建一个名为：TestTable的数据表
        DataTable dt = new DataTable("TestTable");

        //为表创建 4列，分别为： A 、 B 、 C 、 D
        dt.Columns.Add(new DataColumn("A"));
        dt.Columns.Add(new DataColumn("B"));
        dt.Columns.Add(new DataColumn("C"));
        dt.Columns.Add(new DataColumn("D"));

        for (int i = 1; i <= 10; i++)
        {
                //添加新的数据行，并添加数据
                DataRow dr = dt.NewRow();
                dr["A"] = "A_" + i;
                dr["B"] = "B_" + i;
                dr["C"] = "C_" + i;
                dr["D"] = "D_" + i;

                //将此行添加到DataTable中
                dt.Rows.Add(dr);
        }

        return dt;
}