如何根据javascript中的多个字段对数组进行排序答案

【问题标题】：how to sort an array based on multiple fields in javascript如何根据javascript中的多个字段对数组进行排序
【发布时间】：2019-10-28 22:34:40
【问题描述】：

我有一个数组对象

events = [
   {
     year: "2019",
     month: "June",
     title: "title",
     desc: "desc"
   },
   {
     year: "2019",
     month: "June",
     title: "title",
     desc: "desc"
    },
    {
      year: "2019",
      month: "July",
      title: "title",
      desc: "desc"
    },
    {
      year: "2018",
      month: "June",
      title: "title",
      desc: "desc"
     },
     {
       year: "2018",
       month: "March",
       title: "title",
       desc: "desc"
     },
     {
       year: "2018",
       month: "March",
       title: "title",
       desc: "desc"
      }
    ]

如何对数组进行排序以显示相似的年份和月份，我需要在反应组件中使用它，例如一行将显示 2019 年 6 月，另一行显示 2019 年 7 月，然后是 2018 年 6 月，依此类推，

任何帮助将不胜感激

【问题讨论】：

我认为 json 中的 Typo 错误
“相似的年份和月份”是什么意思。你有想要的结果的例子吗？
@NinaScholz，我需要将 2019 年，6 月显示在一行，2019 年 7 月在另一行，2018 年 6 月在另一行等，react 组件完成，我只是无法弄清楚如何对数组进行排序以获得所需的值。
developer.mozilla.org/ru/docs/Web/JavaScript/Reference/…

标签： javascript ecmascript-6

【解决方案1】：

您需要为.sort 提供一个自定义比较器函数，以便使用月份和年份进行排序。

const events = [
   {
     year: "2019",
     month: "June",
     title: "title",
     desc: "desc"
   },
   {
     year: "2019",
     month: "June",
     title: "title",
     desc: "desc"
    },
    {
      year: "2019",
      month: "July",
      title: "title",
      desc: "desc"
    },
    {
      year: "2018",
      month: "June",
      title: "title",
      desc: "desc"
     },
     {
       year: "2018",
       month: "March",
       title: "title",
       desc: "desc"
     },
     {
       year: "2018",
       month: "March",
       title: "title",
       desc: "desc"
      }
];

// Custom comparator function
function sortByMonthYear(a, b) {
	const keyA = `${a.month} ${a.year}`;
	const keyB = `${b.month} ${b.year}`;
	
	if (keyA.localeCompare(keyB)) {
		return -1;
	}
	else if (keyA === keyB) {
		return 0;
	}
	return 1;
}


const grouping = events.sort(sortByMonthYear);

console.log(grouping);

更新：

您还可以使用Array#prototype#reduce 对数据进行分组

const events = [{
    year: "2019",
    month: "June",
    title: "title",
    desc: "desc"
  },
  {
    year: "2019",
    month: "June",
    title: "title",
    desc: "desc"
  },
  {
    year: "2019",
    month: "July",
    title: "title",
    desc: "desc"
  },
  {
    year: "2018",
    month: "June",
    title: "title",
    desc: "desc"
  },
  {
    year: "2018",
    month: "March",
    title: "title",
    desc: "desc"
  },
  {
    year: "2018",
    month: "March",
    title: "title",
    desc: "desc"
  }
];

const grouping = events.reduce((acc, curr) => {
  const key = `${curr.month} ${curr.year}`;
  if (!acc[key]) {
    acc[key] = [curr];
  } else {
    acc[key].push(curr);
  }
  return acc;
}, {});

console.log(grouping);

【讨论】：

感谢您的回答，实际上您之前发布的答案正是我所需要的
@akano1 您能否提供一些您的问题所需的示例输出

【解决方案2】：

通过它们创建对一年中所有月份和flatMap 的引用，在flatMap 中针对原始事件运行过滤器，以仅返回与迭代中的当前月份共享相同month 的任何事件。完成此操作后，您可以在列表中运行 sort 以确保事件按 year 排序（从小到大）

const MOY = ['January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September', 'October', 'November', 'December']
const events = [
 {year: "2019",month: "June",title: "title",desc: "desc"},
 {year: "2019",month: "June",title: "title",desc: "desc"},
 {year: "2019",month: "July",title: "title",desc: "desc"},
 {year: "2018",month: "June",title: "title",desc: "desc"},
 {year: "2018",month: "March",title: "title",desc: "desc"},
 {year: "2018",month: "March",title: "title",desc: "desc"}
]
    
  
const sortedByMonth = MOY.flatMap(m => events.filter(({month}) => m === month))
const sortedByYear = sortedByMonth.sort((eA, eB) => eA.year < eB.year) 
  
console.log(sortedByMonth)
console.log(sortedByYear)

或者，如果您想按月分块，但按年排序，那么就这样做

const MOY = ['January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September', 'October', 'November', 'December']
const events = [
 {year: "2019",month: "June",title: "title",desc: "desc"},
 {year: "2019",month: "June",title: "title",desc: "desc"},
 {year: "2019",month: "July",title: "title",desc: "desc"},
 {year: "2018",month: "June",title: "title",desc: "desc"},
 {year: "2018",month: "March",title: "title",desc: "desc"},
 {year: "2018",month: "March",title: "title",desc: "desc"}
] 
  
const sorted = MOY.flatMap(m => (
  events
  .filter(({month}) => m === month)
  .sort((eA, eB) => eA.year < eB.year)
))
  
console.log(sorted)

【讨论】：