具有相同项目的JavaScript排序数组[重复]

Question

我正在尝试对数组进行排序。我想对它进行排序，以便对于相同的 accountID，我将所有项目存储为一个数组项目。示例输入：

[{accountID: "-Ks8mWWekpN2BfOFcdbS", itemName: "Petrol Charges At Esso"}],
[{accountID: "-Ks8mWWekpN2BfOFcdbS", itemName: "Hylo Lubricant Eye Drops 10ml"}],
[{accountID: "-Ks8mWWekpN2BfOFcdbS", itemName: "Genteal Gel, Sterile Lubricant Eye Gel, 10g"}],
[{accountID: "-Ks8mWWekpN2BfOFcdbS", itemName: "Genteal Gel, Sterile Lubricant Eye Gel, 10g"}],
[{accountID: "-Ks8mWWekpN2BfOFcdbS", itemName: "Blink Intensive Tears Protective Eye Drops 0.4mlx20"}],
[{accountID: "-Ks8mWWekpN2BfOFcdbS", itemName: "Palmers White And Even Dark Circles Eye Treatment Cream 15ml"}],
[{accountID: "-Ks8mWWq445Uao_9sgNn", itemName: "Sensitive Pro-relief With Whitening Toothpaste 110g"}],
[{accountID: "-Ks8mWWq445Uao_9sgNn", itemName: "2 In 1 Pure Breath Toothpaste"}],
[{accountID: "-Ks8mWWq445Uao_9sgNn", itemName: "Antibackterial Mouthwash 200ml"}],
[{accountID: "-Ks8mWWq445Uao_9sgNn", itemName: "Akira 1.7l Jug Kettle Jk1718c"}],
[{accountID: "-Ks8mWWq445Uao_9sgNn", itemName: "Duracell Alkaline Batteries Aaa 12s"}],
[{accountID: "-Ks8mWWq445Uao_9sgNn", itemName: "Osram Led Star Classic A100 Light Bulb - Frosted Warm White 10.5w/827"}],
[{accountID: "-Ks8mWWq445Uao_9sgNn", itemName: "Sharks Fin Soup With Crab Meat And Cordyceps"}],
[{accountID: "-Ks8mWWq445Uao_9sgNn", itemName: "Chilli Fried Rice With Shrimps"}],

要打印到文本文件的所需输出：

['Petrol Charges At Esso', 'Hylo Lubricant Eye Drops 10ml', 'Genteal Gel, Sterile Lubricant Eye Gel, 10g', 'Blink Intensive Tears Protective Eye Drops 0.4mlx20', 'Palmers White And Even Dark Circles Eye Treatment Cream 15ml'],
['Sensitive Pro-relief With Whitening Toothpaste 110g', '2 In 1 Pure Breath Toothpaste', 'Antibackterial Mouthwash 200ml', 'Akira 1.7l Jug Kettle Jk1718c', 'Duracell Alkaline Batteries Aaa 12s', 'Osram Led Star Classic A100 Light Bulb - Frosted Warm White 10.5w/827', 'Sharks Fin Soup With Crab Meat And Cordyceps', 'Chilli Fried Rice With Shrimps'],

我的 JavaScript 代码：

// for simplicity purpose, I do not post the chunk where I resolve the promise. 
promiseKey.then((arr) => {
console.log(arr);
            var result = arr.reduce(function(items, item) {
                var existing = items.find(function(i) {
                    return i.accountID === item.accountID;
                });

                if (existing) {
                    existing.filteredlist.push(item.itemName);
                } else {
                    items.push(item);
                }
            return items;
            }, []);
            console.log('filtered');
            console.log(result);
});

我得到的错误是 Uncaught (in promise) TypeError: Cannot read property 'push' of undefined at the else statement there.

Answer 1

您可以采用更简单的方法，使用 foreach 循环和对象。

var items = {};

arr.forEach(function(item) {

    if(!items.hasOwnProperty(item.accountID)) {
        items[item.accountID] = [];
    }

    items[item.accountID].push(item.itemName);
});

您可以使用Object.keys(items)获取每个帐户的密钥。

Object.keys(items).forEach(function(account) {
    // account is the accountID

    var accountItems = items[account];
});

Answer 2

这里需要在filteredlist使用前进行初始化

更新代码

console.log(arr);
            var result = arr.reduce(function(items, item) {
                var existing = items.find(function(i) {
                    return i.accountID === item.accountID;
                });

                if (existing) {                  
                   existing.filteredlist = [];
                    existing.filteredlist.push(item.itemName);
                } else {
                    items.push(item);
                }
            return items;
            }, []);
            console.log('filtered');
            console.log(result);

这是我的 jsbin 演示 https://jsbin.com/tepedut/edit?js,console

编辑：

根据您的评论，您需要使用accountID 属性对arr 进行排序，您可以使用javascript arr.sort(function(a, b){}); 函数对数组进行排序。

这里是更新的代码

arr.sort(function(a, b){
   if(a.accountID < b.accountID) return -1;
    if(a.accountID > b.accountID) return 1;
    return 0;
});

console.log(arr);

更新了 js bin https://jsbin.com/tepedut/8/edit?js,console