8ee50178f3
Correct: `Array.from()` (it’s a static method) Incorrect: `Array.join()` (doesn’t exist; it’s a prototype method) This patch uses the common `#` syntax to denote `.prototype.`.
24 lines
887 B
Markdown
24 lines
887 B
Markdown
### flattenObject
|
|
|
|
Flatten an object with the paths for keys.
|
|
|
|
Use recursion.
|
|
Use `Object.keys(obj)` combined with `Array.prototype.reduce()` to convert every leaf node to a flattened path node.
|
|
If the value of a key is an object, the function calls itself with the appropriate `prefix` to create the path using `Object.assign()`.
|
|
Otherwise, it adds the appropriate prefixed key-value pair to the accumulator object.
|
|
You should always omit the second argument, `prefix`, unless you want every key to have a prefix.
|
|
|
|
```js
|
|
const flattenObject = (obj, prefix = '') =>
|
|
Object.keys(obj).reduce((acc, k) => {
|
|
const pre = prefix.length ? prefix + '.' : '';
|
|
if (typeof obj[k] === 'object') Object.assign(acc, flattenObject(obj[k], pre + k));
|
|
else acc[pre + k] = obj[k];
|
|
return acc;
|
|
}, {});
|
|
```
|
|
|
|
```js
|
|
flattenObject({ a: { b: { c: 1 } }, d: 1 }); // { 'a.b.c': 1, d: 1 }
|
|
```
|