sectionGroup中的type 可以通过 以下获得
ApplicationSettingsGroup asg = new System.Configuration.ApplicationSettingsGroup();
string asgType = asg .GetType().AssemblyQualifiedName
读取各个节点内容
string searchUrl = ConfigurationManager.AppSettings["CSSP_Hlr_Search"].ToString();
string conString = ConfigurationManager.ConnectionStrings["test"].ToString();
ClientSettingsSection nvc = (ClientSettingsSection)ConfigurationManager.GetSection("testgroup/testsection");
string testName= nvc.Settings.Get("testname1").Value.ValueXml.InnerText.ToString();