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Postgres Javascript承诺不是';t返回修改后的结果_Javascript_Arrays_Postgresql_Nodes_Javascript Objects - Fatal编程技术网

Postgres Javascript承诺不是';t返回修改后的结果

Postgres Javascript承诺不是';t返回修改后的结果,javascript,arrays,postgresql,nodes,javascript-objects,Javascript,Arrays,Postgresql,Nodes,Javascript Objects,我需要一些帮助来理解Javascript承诺。我使用的是postgres,我想要一个函数,该函数将接受一个对象数组,如下例所示 [ { airlineName: 'NZ', { airlineName: 'TN'] 我希望它返回数组,如下所示 [ { airlineName: { iatacode: 'NZ', airlineName: 'Air New Zealand' }, { airlineName: { iatacode: 'TN', airlineName: 'Air Tahit

我需要一些帮助来理解Javascript承诺。我使用的是postgres,我想要一个函数,该函数将接受一个对象数组,如下例所示

[ { airlineName: 'NZ',
  { airlineName: 'TN']
我希望它返回数组,如下所示

[ { airlineName: { iatacode: 'NZ', airlineName: 'Air New Zealand' },
{ airlineName: { iatacode: 'TN', airlineName: 'Air Tahiti Nui' }]
为了简单起见,我在这里简化了查询,但是查询工作正常

如果我在控制台中记录数组,则会出现问题,我将以上面的正确格式获得结果,但是如果我尝试返回语句,则返回undefined

有什么想法吗

exports.extractAirlineName = (flightInfo) => {

    db.many("SELECT airline_name FROM airline_info WHERE iatacode IN 'NZ', 'TN'")
   .then(airline => {
    flightInfo.forEach((flight, index) => {
    flight.airlineName = {
        iatacode: flight.airlineName,
        airlineName: airline[index].airline_name
          };

        // this shows the correctly populated object
          console.log(flightInfo);

            //this just returns undefined
          return flightInfo; 
        });
    });
};

flightInfo
将不定义异步js执行。要处理结果,舒尔需要处理
extractAirlineName
方法
extractAirlineName
无法返回尚不存在的数组。您可以为它返回一个承诺(您已经在构建一个!),购买您需要
返回
它。是我还是缩进?看起来您正试图在
然后
回调中从
forEach
回调返回