问题

我有一个名为pivot的对象，它具有不同深度的多个访问器。

对于键数组const keys = ['rotation']，我希望我的代码像这样分配值x：

pivot['rotation'] = x

对于数组const keys = ['rotation', 'y']，我希望代码执行以下操作：

pivot['rotation']['y'] = x

我尝试的解决方案如下：

accessors.forEach(a => accessor = accessor[a])
accessor = x

然而，在记录accessor值之后，我发现它只是一个原始值0.1，而不是一个对象引用。

我能以某种方式获得对象引用吗？或者我需要采用不同的方法来实现这一点？

可行的代码可能看起来像下面这个丑陋的示例，但这是不可接受的。

if (accessors.length == 1) {
    pivot[accessors[0]] = x
} else if (accessors.length == 2) {
    pivot[accessors[0]][accessors[1]] = x
}

英文:

I have object pivot, that has multiple accessors of different depths.

For keys array const keys = ['rotation'] I want my code to assign value x like this:

pivot[&#39;rotation&#39;] = x

And for array const keys = ['rotation', 'y'] I want the code to do this:

pivot[&#39;rotation&#39;][&#39;y&#39;] = x

Solution I tried looks like this:

accessors.forEach(a =&gt; accessor = accessor[a])
accessor = x

However, after logging the accessor value, I found out it's just primitive value of 0.1, instead of an object reference.

Can I get the object reference somehow? Or do I need to go a different path to achieve this?

Working code would also be something ugly like next example, which is not acceptable.

if (accessors.length == 1) {
    pivot[accessors[0]] = x
} else if (accessors.length == 2) {
    pivot[accessors[0]][accessors[1]] = x
}

答案1

得分: 2

You could reduce the array of keys and preserve the last key as an accessor for assigning the value.

const
    setValue = (reference, keys, value) => {
        const last = keys.pop();
        keys.reduce((o, k) => o[k] ??= {}, reference)[last] = value;
    },
    pivot = {};
setValue(pivot, ['rotation', 'x'], 'y');
console.log(pivot);

英文:

You couldd reduce the array of keys and preserve the last key as accessor for assigning the value.

const
setValue = (reference, keys, value) => {
const last = keys.pop();
keys.reduce((o, k) => o[k] ??= {}, reference)[last] = value;
},
pivot = {};

setValue(pivot, [&#39;rotation&#39;, &#39;x&#39;], &#39;y&#39;);
console.log(pivot);

答案2

得分: 2

这是类似于lodash的set的东西。请记住这会改变对象。

const pivot = {}
const set = (obj, path, value) => {
  const pathLength = path.length;
  path.reduce((acc, key, i) => {
    if (acc[key] === undefined) acc[key] = {}
    if (i === pathLength - 1) acc[key] = value
    return acc[key]
  }, obj)
}
set(pivot, ['rotation', 'x'], 'y');
console.log(pivot);

英文:

here is something similar to lodash set. keep in mind this mutates the object

const pivot = {}
const set = (obj, path, value) =&gt; {
  // Regex explained: https://regexr.com/58j0k
  const pathArray = Array.isArray(path) ? path : path.match(/([^[.\]])+/g)
  const pathLength = pathArray.length;
  pathArray.reduce((acc, key, i) =&gt; {
    if (acc[key] === undefined) acc[key] = {}
    if (i === pathLength - 1) acc[key] = value
    return acc[key]
  }, obj)
}
set(pivot, [&#39;rotation&#39;, &#39;x&#39;], &#39;y&#39;);
console.log(pivot);

since your path is already an array you don't need the regex part

const pivot = {}
const set = (obj, path, value) =&gt; {
  const pathLength = path.length;
  path.reduce((acc, key, i) =&gt; {
    if (acc[key] === undefined) acc[key] = {}
    if (i === pathLength - 1) acc[key] = value
    return acc[key]
  }, obj)
}
set(pivot, [&#39;rotation&#39;, &#39;x&#39;], &#39;y&#39;);
console.log(pivot);