anchor.diff:    //把这个post过来的数据有返回给客户端
     return new shelf.Response.ok('${userName}'    );
   }
  +  Future<shelf.Response> forteaid(shelf.Request request) async {
  +      //从数据库获取数据
  +      String userName1 = await getDataFromDb1();
  +
  +      //把这个post过来的数据有返回给客户端
  +      return new shelf.Response.ok(
  +          ' ${userName1}'
  +      );
  +    }
   
   /*Future<shelf.Response> _echoRequest(shelf.Request request) async {
     //接受post过来的数据
  
positive.code: import 'dart:convert' show JSON;
  import '../lib/stu_class.dart';
  
  Map<String, String> data = new Map();
  Map<String, String> value = new Map();
  final pool = new ConnectionPool(host: "localhost",
      port: 3306,
      user: 'suzyfish',
  
negative.code:    // myRouter.get('/login', forlogin);
      //myRouter.get('/no_login', forno_login);
      myRouter.get('/student/{stuid_x}', forstuid);
      myRouter.get('/teacher/{teaid_x}', forteaid);
      //myRouter.get('/teacher/{teaid_x}/student/{stuid_m}', forteasearch);
  
  
  