我正在開發一個 NodeJS/VueJS 應用程式，我遇到了一些奇怪的行為，我不確定這是我做錯了什么還是其他什么。
我有 2 個陣列，一個包含活動的物件陣列和一個包含與所有活動關聯的所有促銷的物件陣列。
此時，每個 Campaign 物件都包含一個名為 promos 的空陣列，我想在其中推送每個活動的所有促銷活動。
for (var i = 0; i < campaigns.length; i ) {
for (var j = 0; j < campaignsPromo.length; j ) {
if (campaignsPromo.length > 0) {
if (campaigns[i].IDCampaign == campaignsPromo[j].IDCampaign) {
if ((campaignsPromo[j].associated == 1) && (campaignsPromo[j].validated == 1)) {
campaigns[i].promos.push(campaignsPromo[j]);
console.log("Validated Campaign ID " campaigns[i].IDCampaign);
console.log("Promo ID " campaignsPromo[j].IDPromo);
} else if ((campaignsPromo[j].associated == 1) && (campaignsPromo[j].validated == 0)) {
campaigns[i].unvalidatedPromos ;
console.log("Unvalidated Campaign ID " campaigns[i].IDCampaign);
console.log("Promo ID " campaignsPromo[j].IDPromo);
}
}
} else {
console.log("No promos!");
}
}
}
起初，代碼似乎在做應該做的事情，它檢查了我的測驗資料集。但是，最終，所有廣告系列最終都會進行相同的促銷活動。
Campaigns With No Promos: [{"IDCampaign":7,"campaignName":"dadsadafds","startDate":"2022-02-03","endDate":"2022-02-28","unvalidatedPromos":0,"promos":[]},{"IDCampaign":3,"campaignName":"Tarzan 3","startDate":"2022-02-02","endDate":"2022-02-06","unvalidatedPromos":0,"promos":[]},{"IDCampaign":1,"campaignName":"Tarzan","startDate":"2022-02-01","endDate":"2022-03-01","unvalidatedPromos":0,"promos":[]},{"IDCampaign":2,"campaignName":"Tarzan 2","startDate":"2022-02-01","endDate":"2022-02-08","unvalidatedPromos":0,"promos":[]},{"IDCampaign":4,"campaignName":"Tarzan 4","startDate":"2022-02-01","endDate":"2022-02-05","unvalidatedPromos":0,"promos":[]},{"IDCampaign":5,"campaignName":"Jabe 1","startDate":"2022-02-01","endDate":"2022-02-05","unvalidatedPromos":0,"promos":[]},{"IDCampaign":6,"campaignName":"dadsada","startDate":"2022-02-01","endDate":"2022-02-08","unvalidatedPromos":0,"promos":[]},{"IDCampaign":8,"campaignName":"Black Friday","startDate":"2022-02-01","endDate":"2022-02-28","unvalidatedPromos":0,"promos":[]}]
Validated Campaign ID 1
Promo ID 1119
Unvalidated Campaign ID 1
Promo ID 107
Campaigns With Promos: [{"IDCampaign":7,"campaignName":"dadsadafds","startDate":"2022-02-03","endDate":"2022-02-28","unvalidatedPromos":0,"promos":[{"IDCampaign":1,"IDPromo":1119,"promoType":"CHRISTMASS","associated":1,"validated":1,"promoName":"Test Promo 1","beginDate":"2020-11-26","endingDate":"2020-11-29"}]},{"IDCampaign":3,"campaignName":"Tarzan 3","startDate":"2022-02-02","endDate":"2022-02-06","unvalidatedPromos":0,"promos":[{"IDCampaign":1,"IDPromo":1119,"promoType":"CHRISTMASS","associated":1,"validated":1,"promoName":"Test Promo 1","beginDate":"2020-11-26","endingDate":"2020-11-29"}]},{"IDCampaign":1,"campaignName":"Tarzan","startDate":"2022-02-01","endDate":"2022-03-01","unvalidatedPromos":1,"promos":[{"IDCampaign":1,"IDPromo":1119,"promoType":"CHRISTMASS","associated":1,"validated":1,"promoName":"Test Promo 1","beginDate":"2020-11-26","endingDate":"2020-11-29"}]},{"IDCampaign":2,"campaignName":"Tarzan 2","startDate":"2022-02-01","endDate":"2022-02-08","unvalidatedPromos":0,"promos":[{"IDCampaign":1,"IDPromo":1119,"promoType":"CHRISTMASS","associated":1,"validated":1,"promoName":"Test Promo 1","beginDate":"2020-11-26","endingDate":"2020-11-29"}]},{"IDCampaign":4,"campaignName":"Tarzan 4","startDate":"2022-02-01","endDate":"2022-02-05","unvalidatedPromos":0,"promos":[{"IDCampaign":1,"IDPromo":1119,"promoType":"CHRISTMASS","associated":1,"validated":1,"promoName":"Test Promo 1","beginDate":"2020-11-26","endingDate":"2020-11-29"}]},{"IDCampaign":5,"campaignName":"Jabe 1","startDate":"2022-02-01","endDate":"2022-02-05","unvalidatedPromos":0,"promos":[{"IDCampaign":1,"IDPromo":1119,"promoType":"CHRISTMASS","associated":1,"validated":1,"promoName":"Test Promo 1","beginDate":"2020-11-26","endingDate":"2020-11-29"}]},{"IDCampaign":6,"campaignName":"dadsada","startDate":"2022-02-01","endDate":"2022-02-08","unvalidatedPromos":0,"promos":[{"IDCampaign":1,"IDPromo":1119,"promoType":"CHRISTMASS","associated":1,"validated":1,"promoName":"Test Promo 1","beginDate":"2020-11-26","endingDate":"2020-11-29"}]},{"IDCampaign":8,"campaignName":"Black Friday","startDate":"2022-02-01","endDate":"2022-02-28","unvalidatedPromos":0,"promos":[{"IDCampaign":1,"IDPromo":1119,"promoType":"CHRISTMASS","associated":1,"validated":1,"promoName":"Test Promo 1","beginDate":"2020-11-26","endingDate":"2020-11-29"}]}]
這是campaignPromo的內容：
[ { IDCampaign: 1,
IDPromo: 1119,
promoType: 'CHRISTMASS',
associated: 1,
validated: 1,
promoName: 'Test Promo 1',
beginDate: '2020-11-26',
endingDate: '2020-11-29' },
{ IDCampaign: 1,
IDPromo: 107,
promoType: 'CHRISTMASS',
associated: 1,
validated: 0,
promoName: 'Test Promo 2',
beginDate: '2019-12-21',
endingDate: '2019-12-23' } ]
有任何想法嗎？從我的立場來看，我沒有做錯任何事，但這不是我第一次錯過顯而易見的事情。
PS：請忽略我的廣告系列被稱為“泰山”的事實。
uj5u.com熱心網友回復：
你沒有分享有問題的代碼，所以我會給出一個通用的答案。
當癥狀是一堆所有物件似乎具有相同的專案陣列的屬性時，很可能正是由該屬性引起的。每個物件可能共享同一個陣列實體。
一個典型的錯誤如下所示：
var items = [];
var containers = [];
for (let i = 0; i < 3; i) {
items.push(i);
let container = {};
container.items = items;
containers.push(container);
}
console.log(containers);盡管人們可能期望，甚至打算得到 3 個這樣的物件：
[
{專案：[0]}，
{ 專案： [ 0, 1 ] }，
{ 專案： [ 0, 1, 2 ] }
]
items陣列實際上是陣列的同一個實體。而你實際得到的更像是：
[
{ 專案： [ 0, 1, 2 ] },
{ 專案： [ 0, 1, 2 ] },
{ 專案： [ 0, 1, 2 ] }
]
事實上，堆疊片段可視化器實際上在可視化方面做得更好，因為它輸出：
[
{
“專案”： [
/**id:3**/
0,
1、
2
]
},
{
“專案”：/**參考：3**/
},
{
“專案”：/**參考：3**/
}
]
通過這種方式，它試圖通過給它一個標簽來告訴你它實際上是同一個陣列ref:3，并且只是用相同的標簽標記其他屬性的值ref:3作為注釋。
Causes I see typically stem from a misunderstanding of what it means to assign an array to a property. Doing so does not create a copy of the array. Both objects refer to the same array.
This can be strange because: it can appear to be correct in a debugger by inspecting the contents of your array as your are stepping through a loop. Even if we had added log messages like console.log(items) or even console.log(container) inside the loop, we'd probably still not have enough of a clue that something went wrong because the contents of that one array instance change with each iteration of the loop and we can dump versions of it as text that appear to be correct, but then unwittingly change the contents of the array on the next iteration.
But if we log the entire containers array after the loop, you'll find that each object has the same instance of the array. Assining an array isn't bad if it's only one object that gets the array assigned to it, but if you assign the same array to properties of multiple objects, or in a loop, you may run into this problem.
One possible habit-breaker you can try is to inspect all objects in a second loop after your primary loop rather than sneaking your logging code directly into the first loop. It's less efficient, but if you're often making these kinds of mistakes, it can help you find problems and achieve correctness.
Another habit breaker is to console.log(JSON.stringify(foo)) rather than console.log(foo) because console.log in the browser actually remembers the reference of the object and shows you its current contents, rather than its contents at the time it was logged. This is different depending on the platform, where node.js will log as text instead of by reference.
Good luck and be careful!
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