复杂的数组分组 JavaScript
javascriptweb developmentfront end technologyobject oriented programming
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 }
]
