ES6数组:两个数组或数组对象取并集、交集、差集记录贴

数组

取并集

let a=new Set([1,2,3,4,5]);
let b=new Set([1,2,3,4,5,6,7,8,9]);
let arr = Array.from(new Set([...a, ...b]));
console.log('arr',arr);

结果

image

取交集

let a=new Set([1,2,3,4,5]);
let b=new Set([1,2,3,4,5,6,7,8,9]);
let arr = Array.from(new Set([...b].filter(x => a.has(x))));

结果

image

取差集

let a=new Set([1,2,3,4,5]);
let b=new Set([1,2,3,4,5,6,7,8,9]);
let arr = Array.from(new Set([...b].filter(x => !a.has(x))));
console.log('arr',arr);

结果

image

数组对象

取交集

let a=[{id:1,a:123,b:1234},{id:2,a:123,b:1234}];
let b=[{id:1,a:123,b:1234},{id:2,a:123,b:1234},{id:3,a:123,b:1234},{id:4,a:123,b:1234}];
let arr = [...b].filter(x => [...a].some(y => y.id === x.id));
console.log('arr',arr)

结果

image

取差集

let a=[{id:1,a:123,b:1234},{id:2,a:123,b:1234}];
let b=[{id:1,a:123,b:1234},{id:2,a:123,b:1234},{id:3,a:123,b:1234},{id:4,a:123,b:1234}];
let arr = [...b].filter(x => [...a].every(y => y.id !== x.id));
console.log('arr',arr);

结果:

image