freeCodeCamp/curriculum/challenges/chinese/02-javascript-algorithms-and-data-structures/es6/use-destructuring-assignment-to-assign-variables-from-nested-objects.md

---
id: 587d7b89367417b2b2512b4a
title: Use Destructuring Assignment to Assign Variables from Nested Objects
challengeType: 1
forumTopicId: 301214
dashedName: use-destructuring-assignment-to-assign-variables-from-nested-objects
---

# --description--

You can use the same principles from the previous two lessons to destructure values from nested objects.

Using an object similar to previous examples:

```js
const user = {
  johnDoe: { 
    age: 34,
    email: 'johnDoe@freeCodeCamp.com'
  }
};
```

Here's how to extract the values of object properties and assign them to variables with the same name:

```js
const { johnDoe: { age, email }} = user;
```

And here's how you can assign an object properties' values to variables with different names:

```js
const { johnDoe: { age: userAge, email: userEmail }} = user;
```

# --instructions--

Replace the two assignments with an equivalent destructuring assignment. It should still assign the variables `lowToday` and `highToday` the values of `today.low` and `today.high` from the `LOCAL_FORECAST` object.

# --hints--

You should remove the ES5 assignment syntax.

```js
assert(
  !code.match(/lowToday = LOCAL_FORECAST\.today\.low/g) &&
    !code.match(/highToday = LOCAL_FORECAST\.today.high/g)
);
```

You should use destructuring to create the `lowToday` variable.

```js
assert(
  code.match(
    /(var|const|let)\s*{\s*today\s*:\s*{\s*(low\s*:\s*lowToday[^}]*|[^,]*,\s*low\s*:\s*lowToday\s*)}\s*}\s*=\s*LOCAL_FORECAST(;|\s+|\/\/)/g
  )
);
```

You should use destructuring to create the `highToday` variable.

```js
assert(
  code.match(
    /(var|const|let)\s*{\s*today\s*:\s*{\s*(high\s*:\s*highToday[^}]*|[^,]*,\s*high\s*:\s*highToday\s*)}\s*}\s*=\s*LOCAL_FORECAST(;|\s+|\/\/)/g
  )
);
```

`lowToday` should be equal to `64` and `highToday` should be equal to `77`.

```js
assert(lowToday === 64 && highToday === 77);
```

# --seed--

## --seed-contents--

```js
const LOCAL_FORECAST = {
  yesterday: { low: 61, high: 75 },
  today: { low: 64, high: 77 },
  tomorrow: { low: 68, high: 80 }
};

// Only change code below this line

const lowToday = LOCAL_FORECAST.today.low;
const highToday = LOCAL_FORECAST.today.high;

// Only change code above this line
```

# --solutions--

```js
const LOCAL_FORECAST = {
  yesterday: { low: 61, high: 75 },
  today: { low: 64, high: 77 },
  tomorrow: { low: 68, high: 80 }
};

const { today: { low: lowToday, high: highToday }} = LOCAL_FORECAST;
```