JavaScript 将值拆分为数组

Question

我正在创建一个评级系统，它将值四舍五入到最接近的 0.5 并包含 0 到 5 之间的值。

我如何遍历数组，将值(四舍五入到最接近的 0.5)拆分为单位。

让 rating = 3.7

让 adjustedRating = (Math.round(rating * 2)/2);

例如3.7: ['1','1','1','1',0]

1.4 等于 ['1', '0.5', '0', '0', '0']

让 starsToShow = new Array().fill('0');
starsToShow.forEach((v, i) => {
...
});


Answer 1

用 Array.from 做

let rating = 3.7
let adjustedRating = (Math.round(rating * 2) / 2);

console.log(
  Array.from({
    // set array length here
    length: 5
  }, function(_, i) { // iterate over element to update
    // get the difference with index
    var dif = adjustedRating - i;
    // based on the difference assign the array value
    return dif >= 1 ? '1' : dif > 0 ? '0.5' : '0';
  })
);

---

简单的for循环

var rating = 3.7,
  res = [],
  adjustedRating = (Math.round(rating * 2) / 2);

for (var i = 0; i < 5; i++) {
  var dif = adjustedRating - i;
  res.push(dif >= 1 ? '1' : dif > 0 ? '0.5' : '0');
}

console.log(res);