将许多数组合并为一个数组(JavaScript)

时间:2022-03-29 21:14:37

I'm trying to take an array of many arrays that contain many objects and manipulate it into an array of objects.

我正在尝试获取包含许多对象的许多数组的数组,并将其操作为对象数组。

So, let's say I have an array that looks like this:

所以,假设我有一个看起来像这样的数组:

[
    [
        {Name: 'Josh', email: 'josh@gmail.com', Points: 33},
        {Name: 'Doug', email: 'doug@gmail.com', Points: 12}
    ],
    [
        {Name: 'Josh', email: 'josh@gmail.com', Points: 11},
        {Name: 'Doug', email: 'doug@gmail.com', Points: 18}
    ],
    [
        {Name: 'Josh', email: 'josh@gmail.com', Points: 2},
        {Name: 'Doug', email: 'doug@gmail.com', Points: 27}
    ]
]​

The Desired outcome would be an array of objects that has a 'Points' property to hold an array of the points. So it would look like this:

期望的结果将是一个对象数组,其具有'Points'属性来保存点的数组。所以它看起来像这样:

[
    {Name: 'Josh', email: 'josh@gmail.com', Points: [33, 11, 2]},
    {Name: 'Doug', email: 'doug@gmail.com', Points: [12, 18, 27]}
]

This problem seems simple, but I can't seem to figure out the best way of doing this. If you want this data in a fiddle, I made this for you to play with: http://jsfiddle.net/Qhxzz/1/

这个问题看似简单,但我似乎无法弄清楚这样做的最佳方法。如果你想把这些数据放在一个小提琴里,我就让你玩这个:http://jsfiddle.net/Qhxzz/1/

2 个解决方案

#1


2  

Here's one way using .reduce() and .forEach(). (You'll need patches if you're supporting older browsers.)

这是使用.reduce()和.forEach()的一种方法。 (如果您支持旧版浏览器,则需要修补程序。)

var consolidated = data.reduce(function(holder, arr) {
    arr.forEach(function(obj) {
        if (obj.email in holder.emails)
            holder.emails[obj.email].Points.push(obj.Points);
        else {
            holder.emails[obj.email] = obj;
            holder.result.push(obj);
            obj.Points = [obj.Points];
        }
    });
    return holder;
}, {emails:{},result:[]}).result;

And actually, we could flatten out the original Array using concat.apply(), and be left with one monolithic Array to iterate.

实际上,我们可以使用concat.apply()来展平原始数组,并留下一个单片阵列进行迭代。

flat = [].concat.apply([], data);

This turns your data into this structure:

这会将您的数据转换为此结构:

[{Name:"Josh", email:"josh@gmail.com", Points:33},
 {Name:"Doug", email:"doug@gmail.com", Points:12},
 {Name:"Josh", email:"josh@gmail.com", Points:11},
 {Name:"Doug", email:"doug@gmail.com", Points:18},
 {Name:"Josh", email:"josh@gmail.com", Points:2},
 {Name:"Doug", email:"doug@gmail.com", Points:27}]

And makes the consolidation a bit simpler by eliminating the need for the inner .forEach().

通过消除内部.forEach()的需要,使合并更简单一些。

var consolidated = flat.reduce(function(holder, obj) {
    if (obj.email in holder.emails)
        holder.emails[obj.email].Points.push(obj.Points);
    else {
        holder.emails[obj.email] = obj;
        holder.result.push(obj);
        obj.Points = [obj.Points];
    }
    return holder;
}, {emails:{}, result:[]}).result;

#2


2  

Note that this depends on the input structure being static (no recursion here). Assuming you're not using any libraries:

请注意,这取决于输入结构是静态的(这里没有递归)。假设您没有使用任何库:

var result = [];

for (var i = 0; i < initial.length; i++) {
    var innerArray = initial[i];

    for (var j = 0; j < innerArray.length; j++) {
        var item = innerArray[j];

        var found = false;
        // search result for an object with a matching email prop
        for (var k = 0; k < result.length; k++) {
            if (result[k].email === item.email) {
                found = true;

                // add this Point to the Points array
                result[k].Points.push(item.Points);
            }
        }

        if (!found) {
            // convert Points to an array of Points
            item.Points = [item.Points];

            result.push(item);
        }
    }
}

http://jsfiddle.net/Qhxzz/2/

#1


2  

Here's one way using .reduce() and .forEach(). (You'll need patches if you're supporting older browsers.)

这是使用.reduce()和.forEach()的一种方法。 (如果您支持旧版浏览器,则需要修补程序。)

var consolidated = data.reduce(function(holder, arr) {
    arr.forEach(function(obj) {
        if (obj.email in holder.emails)
            holder.emails[obj.email].Points.push(obj.Points);
        else {
            holder.emails[obj.email] = obj;
            holder.result.push(obj);
            obj.Points = [obj.Points];
        }
    });
    return holder;
}, {emails:{},result:[]}).result;

And actually, we could flatten out the original Array using concat.apply(), and be left with one monolithic Array to iterate.

实际上,我们可以使用concat.apply()来展平原始数组,并留下一个单片阵列进行迭代。

flat = [].concat.apply([], data);

This turns your data into this structure:

这会将您的数据转换为此结构:

[{Name:"Josh", email:"josh@gmail.com", Points:33},
 {Name:"Doug", email:"doug@gmail.com", Points:12},
 {Name:"Josh", email:"josh@gmail.com", Points:11},
 {Name:"Doug", email:"doug@gmail.com", Points:18},
 {Name:"Josh", email:"josh@gmail.com", Points:2},
 {Name:"Doug", email:"doug@gmail.com", Points:27}]

And makes the consolidation a bit simpler by eliminating the need for the inner .forEach().

通过消除内部.forEach()的需要,使合并更简单一些。

var consolidated = flat.reduce(function(holder, obj) {
    if (obj.email in holder.emails)
        holder.emails[obj.email].Points.push(obj.Points);
    else {
        holder.emails[obj.email] = obj;
        holder.result.push(obj);
        obj.Points = [obj.Points];
    }
    return holder;
}, {emails:{}, result:[]}).result;

#2


2  

Note that this depends on the input structure being static (no recursion here). Assuming you're not using any libraries:

请注意,这取决于输入结构是静态的(这里没有递归)。假设您没有使用任何库:

var result = [];

for (var i = 0; i < initial.length; i++) {
    var innerArray = initial[i];

    for (var j = 0; j < innerArray.length; j++) {
        var item = innerArray[j];

        var found = false;
        // search result for an object with a matching email prop
        for (var k = 0; k < result.length; k++) {
            if (result[k].email === item.email) {
                found = true;

                // add this Point to the Points array
                result[k].Points.push(item.Points);
            }
        }

        if (!found) {
            // convert Points to an array of Points
            item.Points = [item.Points];

            result.push(item);
        }
    }
}

http://jsfiddle.net/Qhxzz/2/