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javascript - 您如何比较 JS 中的“周年”值？

问题描述

例如，我有以下String周年格式的值：

// week-year
"8-18" < "9-18"   // returns true
"8-18" < "10-18"  // returns false but should return true
"8-18" < "4-18"   // returns false but should be true

为了调度目的，我必须整理出具有“周年”值的数组数组。目前我正在使用array.sort来完成这个：

var results = [
  [ 
    { weekyear:"4-18" } 
  ], 
  [
    { weekyear:"5-18" }
  ], 
  [
    { weekyear: "1-19" }
  ] ... ]

results.sort((function (index) { // Sort based on Week-Year in descending order 
  return function (a, b) {
    return (a[index].weekyear === b[index].weekyear ? 0 : (a[index].weekyear< b[index].weekyear ? -1 : 1));
  };
})(0));

有什么办法可以将week-year值修改为允许排序的数值？

上面的排序应该按顺序给我： 

"1-19" , "5-18" , "4-18"

标签： javascriptcomparisondate-comparison

解决方案

您可以创建一个格式化的字符串，其中年份首先出现，然后是填充的一周，可以将其作为字符串进行比较。

function getYearWeek(weekYear) {
    return weekYear
        .split('-')
        .map(s => s.padStart(2, '0'))
        .reverse()
        .join('-W');
}

var results = [{ weekyear: "4-20" }, { weekyear: "5-18" }, { weekyear: "4-18" }, { weekyear: "1-19" }];

console.log(getYearWeek("8-18") < getYearWeek("9-18"));  // true
console.log(getYearWeek("8-18") < getYearWeek("10-18")); // true
console.log(getYearWeek("8-18") < getYearWeek("4-18"));  // false

results.sort((a, b) => 
    getYearWeek(a.weekyear).localeCompare(getYearWeek(b.weekyear)));

console.log(results);
.as-console-wrapper { max-height: 100% !important; top: 0; }

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