如何实现一个数组按照另外一个数组的顺序进行排序?
数组arr1按照arr2的顺序展示,如何实现:
一、简单类型数组
let arr1 = [1, 2, 3, 4, 5]
let arr2 = [5, 3, 2, 4, 1]
arr1.sort((prev,next)=>{ return arr2.indexOf(prev)-arr2.indexOf(next) }) console.log(arr1) // [5, 3, 2, 4, 1]
二、复杂类型数组
let arr1 = [ { id: 1, name: '小米' }, { id: 3, name: '小红' }, { id: 4, name: '小明' }, { id: 2, name: '小华' } ]
let arr1 = [ { id: 1, name: '小米' }, { id: 2, name: '小华' }, { id: 3, name: '小红' }, { id: 4, name: '小明' } ]
方法一:
let sortIndex = arr2.map(item => item.id) arr1.sort((a, b) => sortIndex.indexOf(a.id) - sortIndex.indexOf(b.id)) console.log(arr1)
方法二:
let order = new Map(twoArr.map((item, index) => [item.intID, index]));
arr1.sort((a, b) => { let orderA = order.has(a.id) ? order.get(a.id) : Infinity; let orderB = order.has(b.id) ? order.get(b.id) : Infinity; return orderA - orderB; }); console.log(arr1)
方法三: const newArr = []; arr2.forEach((twoE) => { arr1.forEach((oneE) => { if (twoE.id === oneE.id) { newArr.push(oneE); } }); }); console.log(newArr)
方法四: const cache = {}; arr1.sort((a, b) => { const aId = a.id, bId = b.id; let aIndex = cache[aId] ?? -1; let bIndex = cache[bId] ?? -1; if (aIndex < 0 || bIndex < 0) { for (let i = 0; i < arr2.length; ++i) { const id = arr2[i].id; if (aId === id) aIndex = cache[aId] = i; if (bId === id) bIndex = cache[bId] = i; if (aIndex >= 0 && bIndex >= 0) break; } } return aIndex - bIndex; }); console.log(arr1)
结果: