hasNext 不能在 javascript 中收集 [英] hasNext not working on collection in javascript

问题描述

我在 javascript 中有以下代码可以检索两行:

I have following code in javascript which retrieves two rows:

 var raceCursor = RacesCollection.find({eventId: "e1"});
    var race;
    while(raceCursor.hasNext()){
    race = raceCursor.next();                   
    console.log(race.raceName);
    }

看起来没什么问题，但它显示:

Seems nothing wrong with it, but it shows :

Uncaught TypeError: Object [object Object] 在 javascript 控制台中没有方法 'hasNext'.

我在这里缺少什么?

MongoDB 方法是否需要在 javascript 中进行特殊导入才能用于集合??

Do the MongoDB methods requires special imports in javascript, in order to be used on the collections??

集合是:

RacesCollection  = new Meteor.Collection("RacesCollection");
RacesCollection.insert({raceId:"r1", eventId:"e1", raceName:"Moto race 1", status:"statusDetail"});
RacesCollection.insert({raceId:"r2", eventId:"e1", raceName:"Moto race 2", status:"statusDetail"});

任何建议都会被采纳.谢谢..

Any recommendation will be appriciated. thanks..

推荐答案

根据 Meteor docs 迭代一个的正确方法游标是 cursor.forEach().游标也没有 hasNext() 或 next() 方法.

According to Meteor docs the proper way to iterate a cursor is cursor.forEach(). Also cursors don't have hasNext() or next() methods.

所以在你的情况下它应该是:

So in your case it should read:

var raceCursor = RacesCollection.find({eventId: "e1"});

raceCursor.forEach(function(race) {
    console.log(race.raceName);    
});

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