javascript - 标记数组中的重复项

Question

在请求了一些用户图片后，我得到了一个这样的数组:

[
    { label: "portrait", owner: "Jon" },
    { label: "house", owner: "Jim" },
    { label: "portrait", owner: "Jim" },
    { label: "portrait", owner: "Jane" },
    { label: "cat", owner: "Jane" }
]

我需要突出显示其 label 在数组中出现多次的项目(此处:“portrait”)。

理想情况下，label 在数组中 later 再次出现的项目会有一个标志 (A)，最后一次出现 (即 Jon 和 Jim 的肖像都标记为 A，而 Jane 的肖像标记为 B)。

如有任何帮助，我们将不胜感激!

Answer 1

我不确定您要做什么，但也许您只需要聚合数据？

var data = [
    { name: "portrait", owner: "Jon" },
    { name: "house", owner: "Jim" },
    { name: "portrait", owner: "Jim" },
    { name: "portrait", owner: "Jane" },
    { name: "cat", owner: "Jane" }
];

var byName = {};

for (var i = 0, l = data.length; i < l; ++i) {
    if (!byName[data[i].name]){
        byName[data[i].name] = [];
    }
    byName[data[i].name].push(data[i].owner);
}

// byName == {portrait: ["Jon", "Jim", "Jane"], house: ["Jim"], cat: ["Jane"]}

var byOwner = {};

for (var i = 0, l = data.length; i < l; ++i) {
    if (!byOwner[data[i].owner]) {
        byOwner[data[i].owner] = [];
    }
    byOwner[data[i].owner].push(data[i].name);
}

---

或者你可能更喜欢这个:

var data = [
    { name: "portrait", owner: "Jon" },
    { name: "house", owner: "Jim" },
    { name: "portrait", owner: "Jim" },
    { name: "portrait", owner: "Jane" },
    { name: "cat", owner: "Jane" }
];

var byName = [];

for (var i = 0, l = data.length; i < l; ++i) {
    var done = false;
    for (var j = 0, k = data.length; j < k; ++j) {
        if (byName[j] && byName[j].name == data[i].name) {
            byName[j].data.push(data[i].owner);
            done = true;
        }
    }
    if (!done) {
        byName.push({name: data[i].name, data: [data[i].owner]});
    }
}

/*
byName == [
    {name: "portrait", data: ["Jon", "Jim", "Jane"]},
    {name: "house", data: ["Jim"]},
    {name: "cat", data: ["Jane"]}
] */

因为发布随机代码很有趣而且你知道这一点!