相关疑难解决方法(0)

谁能解释一下,为什么ES6阵列解构会发生以下情况？

let a, b, c
[a, b] = ['A', 'B']
[b, c] = ['BB', 'C']
console.log(`a=${a} b=${b} c=${c}`)

// expected: a=A b=BB c=C
// actual:   a=BB b=C c=undefined

http://codepen.io/ronkot/pen/WxRqXg?editors=0011

我有以下代码

const integerDivide = (a, b) => {
  return [Math.floor(a / b), a % b]
}


let sec = 555003,
  min, hr, day;

[min, sec] = integerDivide(sec, 60)
console.log(`sec: ${sec}`)
console.log(`min: ${min}`)
[hr, min] = integerDivide(min, 60)
console.log(`hr: ${hr}`)

此代码给出以下错误

Uncaught TypeError: Cannot set property '9250' of undefined

我不明白为什么这段代码不起作用。任何解释或更正将不胜感激。下面是代码笔链接 https://codepen.io/devbkhadka/pen/ExyyEWE?editors=1111