我稍微扩展了@IgorL的解决方案,但是扩展了原型并给它一个选择器函数而不是属性,以使其更加灵活:
Array.prototype.unique = function(selector) {
return this.filter((e, i) => this.findIndex((a) => {
if (selector) {
return selector(a) === selector(e);
}
return a === e;
}) === i);
};
用法:
// with no param it uses strict equals (===) against the object
let primArr = ['one','one','two','three','one']
primArr.unique() // ['one','two','three']
let a = {foo:123}
let b = {foo:123}
let fooArr = [a,a,b]
fooArr.unique() //[a,b]
// alternatively, you can pass a selector function
fooArr.unique(item=>item.foo) //[{foo:123}] (first "unique" item returned)
这绝不是最高效的方法,但只要选择器简单且数组不是很大,它就可以正常工作。
在TypeScript中
Array.prototype.unique = function<T>(this: T[], selector?: (item: T) => object): T[] {
return this.filter((e, i) => this.findIndex((a) => {
if (selector) {
return selector(a) === selector(e);
}
return a === e;
}) === i);
};