一.去重前后数据对比
// 原数据是这样的
[{
"goodsId": "1", "quota": 12, "skuId": "1" },
{ "goodsId": "2", "quota": 12, "skuId": "2" },
{ "goodsId": "1", "quota": 12, "skuId": "1" }]
// 去重后数据是这样的
[{
"goodsId": "1", "quota": 12, "skuId": "1" },
{ "goodsId": "2", "quota": 12, "skuId": "2" }]
二.使用方法
1.使用filter和Map 代码简洁
function uniqueFunc(arr, uniId){
const res = new Map();
return arr.filter((item) => !res.has(item[uniId]) && res.set(item[uniId], 1));
}
2.使用reduce 代码稍多
function uniqueFunc2(arr, uniId){
let hash = {} return arr.reduce((accum,item) => {
hash[item[uniId]] ? '' : hash[item[uniId]] = true && accum.push(item)
return accum },[])
}
3.使用for循环 耗费时间较一二稍多
function uniqueFunc3(arr, uniId){
let obj = {} let tempArr = [] for(var i = 0; i<arr.length; i++){
if(!obj[arr[i][uniId]]){
tempArr.push(arr[i]) obj[arr[i][uniId]] = true }
}
return tempArr
}
const books = [
{ name: "My Sister the Serial Killer", author: "Oyinkan Braithwaite" },
{ name: "Educated", author: "Tara Westover" },
{ name: "My Sister the Serial Killer", author: "Oyinkan Braithwaite" }];
function unique(arr) {
let unique = {};
arr.forEach(function(item) {
unique[JSON.stringify(item,['name','author'])] = item; //键名顺序问题
})
arr = Object.keys(unique).map(function(u) {
//Object.keys()返回对象的所有键值组成的数组，map方法是一个遍历方法，返回遍历结果组成的数组.
//将unique对象的键名还原成对象数组
return JSON.parse(u);
})
return arr;
}
function removeDuplicate_10(arr, attr) {
const result = new Map(); return arr.filter((item) => !result.has(item[attr]) && result.set(item[attr], 1))
}
removeDuplicate_10（数组，重复参数名）
