static void Main()
{
DataTable dt = new DataTable();
dt.Columns.Add("c1", typeof(int));
dt.Columns.Add("c2", typeof(string));
dt.Columns.Add("c3", typeof(int));
dt.Rows.Add(1, "技术部", 130);
dt.Rows.Add(2, "产品部", 200);
dt.Rows.Add(3, "市场部", 130);
dt.Rows.Add(3, "市场部", 30);
var query = from d in dt.AsEnumerable()
group d by d.Field<string>("c2") into g
select new
{
c2 = g.Key,
c3 = g.Sum(t => t.Field<int>("c3"))
};
query.ToList().ForEach(q => Console.WriteLine("{0},{1}", q.c2, q.c3));
}