while循环和callback返回不同的结果
我有一个while循环匹配一个条件来过滤来自MongoDB的数据。 但是，当我使用callback时，我只收到一个结果到console.log 。 如果我在while循环中使用console.log，我应该得到三个条目。 为什么只有一个数据使其callback？
while(i--) { if (0 >= [friday, saturday, sunday].indexOf(results[i].selectedDate)) { theWeekend = results[i]; console.log(theWeekend); //returns three results (correct) } } callback(err, theWeekend) console.log(theWeekend); //returns one results (incorrect)
正确的数据
{ _id: 56fffb5ceb76276c8f39e3f3, url: 'http://londonist.com/2015/11/where-to-eat-and-drink-in-balham', title: 'Where To Eat And Drink In... Balham | Londonist', selectedDate: Fri Apr 01 2016 01:00:00 GMT+0100 (BST), __v: 0 } { _id: 56fffb8eeb76276c8f39e3f5, url: 'https://news.ycombinator.com/item?id=11404770', title: 'The Trouble with CloudFlare | Hacker News', selectedDate: Sun Apr 03 2016 01:00:00 GMT+0100 (BST), __v: 0 } { _id: 56fffb6ceb76276c8f39e3f4, url: 'http://wellnessmama.com/13700/benefits-coconut-oil-pets/', title: 'Benefits of Coconut Oil for Pets - Wellness Mama', selectedDate: Sat Apr 02 2016 01:00:00 GMT+0100 (BST), __v: 0 }
不正确的数据
{ _id: 56fffb6ceb76276c8f39e3f4, url: 'http://wellnessmama.com/13700/benefits-coconut-oil-pets/', title: 'Benefits of Coconut Oil for Pets - Wellness Mama', selectedDate: Sat Apr 02 2016 01:00:00 GMT+0100 (BST), __v: 0 }
您需要使用数组来存储所有结果，如下所示：
var theWeekends = [] while(i--) { if (0 >= [friday, saturday, sunday].indexOf(results[i].selectedDate)) { theWeekends.push(results[i]); } } callback(err, theWeekends) console.log(theWeekends); //returns 3 results (correct)