我有一个包含对象数组的对象。
obj = {};
obj.arr = new Array();
obj.arr.push({place:"here",name:"stuff"});
obj.arr.push({place:"there",name:"morestuff"});
obj.arr.push({place:"there",name:"morestuff"});
我想知道从数组中删除重复对象的最佳方法是什么。例如,obj.arr将变成。。。
{place:"here",name:"stuff"},
{place:"there",name:"morestuff"}
我认为,将reduce与JSON.stringify结合起来以完美地比较对象,并选择性地添加那些尚未在累加器中的对象是一种优雅的方式。
请记住,在极端情况下,JSON.stringify可能会成为一个性能问题,因为阵列有许多对象,而且它们很复杂,但在大多数情况下,这是IMHO的最短路径。
var集合=〔{a:1},{a:2},{a:1},{a:3}〕var filtered=collection.reduce((已过滤,项)=>{if(!filtered.some(filteredItem=>JSON.stringify(filtered item)==JSON.sstringify(item)))已过滤推送(项)返回已过滤}, [])console.log(已过滤)
另一种写法相同(但效率较低):
collection.reduce((filtered, item) =>
filtered.some(filteredItem =>
JSON.stringify(filteredItem ) == JSON.stringify(item))
? filtered
: [...filtered, item]
, [])
这里是ES6的解决方案,您只想保留最后一项。该解决方案功能强大,符合Airbnb风格。
const things = {
thing: [
{ place: 'here', name: 'stuff' },
{ place: 'there', name: 'morestuff1' },
{ place: 'there', name: 'morestuff2' },
],
};
const removeDuplicates = (array, key) => {
return array.reduce((arr, item) => {
const removed = arr.filter(i => i[key] !== item[key]);
return [...removed, item];
}, []);
};
console.log(removeDuplicates(things.thing, 'place'));
// > [{ place: 'here', name: 'stuff' }, { place: 'there', name: 'morestuff2' }]
来源
JSFiddle公司
这将在不传递任何键的情况下删除重复对象。
uniqueArray=a=>[…new Set(.map(o=>JSON.stringify(o))].map(s=>JSON.parse(s));var objects=[{'x':1,'y':2},{'x':2,'y':1},{'x':1,'y':2}];var unique=uniqueArray(对象);console.log(“原始对象”,对象);console.log(“唯一”,唯一);
uniqueArray = a => [...new Set(a.map(o => JSON.stringify(o)))].map(s => JSON.parse(s));
var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }, { 'x': 1, 'y': 2 }];
var unique = uniqueArray(objects);
console.log(objects);
console.log(unique);
const uniqueElements = (arr, fn) => arr.reduce((acc, v) => {
if (!acc.some(x => fn(v, x))) { acc.push(v); }
return acc;
}, []);
const stuff = [
{place:"here",name:"stuff"},
{place:"there",name:"morestuff"},
{place:"there",name:"morestuff"},
];
const unique = uniqueElements(stuff, (a,b) => a.place === b.place && a.name === b.name );
//console.log( unique );
[{
"place": "here",
"name": "stuff"
},
{
"place": "there",
"name": "morestuff"
}]