Javascript NodeJS 计算数组中有多少个对象？
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NodeJS Count how many objects in array?
提问by prk
How would I count how many objects there are inside an array?
我如何计算数组中有多少个对象？
The array looking like:
数组看起来像：
[ {id: 1}, {id: 2}, ...]
I assume I could use count() if it was PHP, but what about NodeJS/Javascript?
我假设如果是 PHP，我可以使用 count()，但是 NodeJS/Javascript 呢？
Edit:
编辑：
if (offer.items_to_receive.length > 0) {
console.log("items: " + offer.items_to_receive.length);
for(var i = 0; i < offer.items_to_receive.length; i++) {
usersInRound.push(offer.steamid_other);
}
}
logData('Accepted trade offer from ' + offer.steamid_other + '. (tradeofferid: ' + offer.tradeofferid + ')\nWorth ' + offer.items_to_receive.length + ' tickets. ');
How come it can read the "worth X tickets", but not the other part?
为什么它可以读取“价值X票”，而不能读取其他部分？
回答by Alexander T.
Use .length
用 .length
var data = [{
id: 1
}, {
id: 2
}];
console.log(data.length);Update, in your edit I see that
更新，在您的编辑中我看到
offer.items_to_receiveis undefined, ensure that object offerhas property items_to_receive(should be array);
offer.items_to_receiveis undefined，确保对象offer有属性items_to_receive（应该是数组）；
回答by Zuber Surya
list = //YOUR OBJECT DATA
count= Object.keys(list).length;
count= Object.keys(list).length;
Object.keys() gives the count of keys
That should give proper count
那应该给出适当的计数
回答by Sheharyar
I think your question should be How to get Array Size in Javascript?
我认为您的问题应该是如何在 Javascript 中获取数组大小？
Answer:Use the lengthmethod.
答：使用length方法。
Examples:
例子：
[1,2,3].length
// => 3
var a = { num: 1, obj: {}, arr: [{}, 3, "asd", {q: 3}, 1] }
a.arr.length
// => 5
