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"}
带过滤器的内衬(保留订单)
在数组中查找唯一id。
arr.filter((v,i,a)=>a.findIndex(v2=>(v2.id===v.id))===i)
如果顺序不重要,映射解决方案将更快:使用映射解决方案
多个财产独有(地点和名称)
arr.filter((v,i,a)=>a.findIndex(v2=>['place','name'].every(k=>v2[k] ===v[k]))===i)
所有财产都是唯一的(对于大型阵列来说,这将很慢)
arr.filter((v,i,a)=>a.findIndex(v2=>(JSON.stringify(v2) === JSON.stringify(v)))===i)
通过用findLastIndex替换findIndex来保留最后一次出现。
arr.filter((v,i,a)=>a.findLastIndex(v2=>(v2.place === v.place))===i)
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"
}]