复杂的数组分组 JavaScript

假设我们有一个像这样的对象数组 −

const arr = [
   {userId: "3t5bsFB4PJmA3oTnm", from: 1, to: 6},
   {userId: "3t5bsFB4PJmA3oTnm", from: 7, to: 15},
   {userId: "3t5bsFB4PJmA3oTnm", from: 172, to: 181},
   {userId: "3t5bsFB4PJmA3oTnm", from: 182, to: 190}
];

我们需要编写一个 JavaScript 函数来接收一个这样的数组。该函数应根据重叠对象的 "from" 和 "to" 属性将其分组为单个对象，就像这样 −

const output = [
   {userId: "3t5bsFB4PJmA3oTnm", from: 1, to: 15},
   {userId: "3t5bsFB4PJmA3oTnm", from: 172, to: 190}
];

示例

const arr = [
   {userId: "3t5bsFB4PJmA3oTnm", from: 1, to: 6},
   {userId: "3t5bsFB4PJmA3oTnm", from: 7, to: 15},
   {userId: "3t5bsFB4PJmA3oTnm", from: 172, to: 181},
   {userId: "3t5bsFB4PJmA3oTnm", from: 182, to: 190}
];
const groupByDuration = (arr = []) => {
   const result = arr.reduce((acc, val) => {
      let last = acc[acc.length - 1] || {};
      if (last.userId === val.userId && last.to + 1 === val.from) {
         last.to = val.to; } else {
            acc.push({ userId: val.userId, from: val.from, to: val.to });
      }
      return acc;
   }, []);
   return result;
}
console.log(groupByDuration(arr));

输出

控制台中的输出将是 −

[
   { userId: '3t5bsFB4PJmA3oTnm', from: 1, to: 15 },
   { userId: '3t5bsFB4PJmA3oTnm', from: 172, to: 190 }
]

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有用资源

• javascript 参考教程 - 该教程包含有关 javascript 的更多信息:https://www.cainiaomax.com/javascript/