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

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id, title, challengeType, videoUrl, localeTitle
id title challengeType videoUrl localeTitle
587d7b89367417b2b2512b4a Use Destructuring Assignment to Assign Variables from Nested Objects 1 使用解构分配从嵌套对象分配变量

Description

我们可以类似地将嵌套对象解构为变量。请考虑以下代码:
const a = {
开始:{x5y6}
结束:{x6y-9}
};
const {start{xstartXystartY}} = a;
console.logstartXstartY; // 5,6
在上面的示例中,变量start被赋予a.start的值,该值也是一个对象。

Instructions

用解构赋值来获得maxforecast.tomorrow并将其分配给maxOfTomorrow

Tests

tests:
  - text: <code>maxOfTomorrow</code>等于<code>84.6</code>
    testString: 'assert(getMaxOfTmrw(LOCAL_FORECAST) === 84.6, "<code>maxOfTomorrow</code> equals <code>84.6</code>");'
  - text: 使用嵌套解构
    testString: 'getUserInput => assert(getUserInput("index").match(/\{\s*tomorrow\s*:\s*\{\s*max\s*:\s*maxOfTomorrow\s*\}\s*\}\s*=\s*forecast/g),"nested destructuring was used");'

Challenge Seed

const LOCAL_FORECAST = {
  today: { min: 72, max: 83 },
  tomorrow: { min: 73.3, max: 84.6 }
};

function getMaxOfTmrw(forecast) {
  "use strict";
  // change code below this line
  const maxOfTomorrow = undefined; // change this line
  // change code above this line
  return maxOfTomorrow;
}

console.log(getMaxOfTmrw(LOCAL_FORECAST)); // should be 84.6

Solution

// solution required