javascript - 根据当前日期排序数组

Question

我正在尝试根据今天的日期对下面的数组重新排序:

[
    {
        "index": "0",
        "day": "Monday",
        "food": "Salad"
    },
    {
        "index": "1",
        "day": "Friday",
        "food": "Pasta"
    },
    {
        "index": "2",
        "day": "Sunday",
        "food": "Pasta"
    },
    {
        "index": "3",
        "day": "Thursday",
        "food": "Pasta"
    },
    {
        "index": "4",
        "day": "Tuesday",
        "food": "Pasta"
    },
    {
        "index": "2",
        "day": "Sunday",
        "food": "Pasta"
    },
    {
        "index": "5",
        "day": "Wednesday",
        "food": "Pasta"
    },
    {
        "index": "6",
        "day": "Saturday",
        "food": "Pasta"
    }
]

假设今天是星期六，排序后，项目索引的预期输出为:6, 2, 2, 0, 4, 5, 3, 1如果今天是 星期二，则按索引输出为:4, 5, 3, 1, 6, 2, 2, 0

我正在使用 moment.js，到目前为止我还没有为此创建一个不庞大的代码。最后，我想将代码包装在自定义 orderBy 过滤器中，以用于 ng-repeat 指令。

Answer 1

这是我想出的最小解决方案:

const DAYS = { 'Sunday': 0, 'Monday': 1, 'Tuesday': 2, 'Wednesday': 3, 'Thursday': 4, 'Friday': 5, 'Saturday': 6 };

// Get the relative index of a day using today as a reference.
function relativeIndex(day) {
  const TODAY = new Date().getDay();
  return (DAYS[day] - TODAY + 7) % 7;
}

// Sort a lit of data starting by today.
function sort(data) {
  return data.sort((a, b) => relativeIndex(a.day) - relativeIndex(b.day));
}

这里的关键是 relativeIndex 函数，它使用今天作为引用来计算任何一天的指数。