求帮忙注释、、、新手 看不懂
/*SqlConnection conn = new SqlConnection("Data Source=.;Initial Catalog=UserInfo;User ID=sa;Password=1234");
SqlCommand com = conn.CreateCommand();
= "select * from Department";
SqlDataAdapter da = new SqlDataAdapter();
da.SelectCommand = com;
DataSet ds= new DataSet();
conn.Open();
da.Fill(ds);
conn.Close();
*/