我有一个目标数组[“apple”、“banana”、“orange”],我想检查其他数组是否包含任何一个目标阵列元素。

例如:

["apple","grape"] //returns true;

["apple","banana","pineapple"] //returns true;

["grape", "pineapple"] //returns false;

如何在JavaScript中实现?


当前回答

如果你不反对使用图书馆,http://underscorejs.org/有一种相交方法,可以简化这一点:

var _ = require('underscore');

var target = [ 'apple', 'orange', 'banana'];
var fruit2 = [ 'apple', 'orange', 'mango'];
var fruit3 = [ 'mango', 'lemon', 'pineapple'];
var fruit4 = [ 'orange', 'lemon', 'grapes'];

console.log(_.intersection(target, fruit2)); //returns [apple, orange]
console.log(_.intersection(target, fruit3)); //returns []
console.log(_.intersection(target, fruit4)); //returns [orange]

交集函数将返回一个包含匹配项的新数组,如果不匹配,则返回空数组。

其他回答

我在node中使用下划线js提出了一个解决方案,如下所示:

var checkRole = _.intersection(['A','B'], ['A','B','C']);
if(!_.isEmpty(checkRole)) { 
     next();
}

您正在寻找两个数组之间的交集。你有两种主要的交叉点类型:“每个”和“一些”。让我举几个好例子:

let brands1 = ['Ford', 'Kia', 'VW', 'Audi'];
let brands2 = ['Audi', 'Kia'];
// Find 'every' brand intersection. 
// Meaning all elements inside 'brands2' must be present in 'brands1':
let intersectionEvery = brands2.every( brand => brands1.includes(brand) );
if (intersectionEvery) {
    const differenceList = brands1.filter(brand => !brands2.includes(brand));
    console.log('difference list:', differenceList);
    const commonList = brands1.filter(brand => brands2.includes(brand));
    console.log('common list:', commonList);
}

如果条件不满足(比如你在品牌中加入了“梅赛德斯”),那么“intersectionEvery”就不满足了——这将是错误的。

如果满足条件,它将把[“福特”、“大众”]列为区别,把[“起亚”、“奥迪”]列为了常见列表。

沙盒:https://jsfiddle.net/bqmg14t6/

SOME

let brands1 = ['Ford', 'Kia', 'VW', 'Audi'];
let brands2 = ['Audi', 'Kia', 'Mercedes', 'Land Rover'];
// Find 'some' brand intersection. 
// Meaning some elements inside 'brands2' must be also present in 'brands1':
let intersectionSome = brands2.some( brand => brands1.includes(brand) );
if (intersectionSome) {
    const differenceList = brands1.filter(brand => !brands2.includes(brand));
    console.log('difference list:', differenceList);
    const commonList = brands1.filter(brand => brands2.includes(brand));
    console.log('common list:', commonList);
}

我们在这里寻找一些常见的品牌,但不一定全部。

它将把[“福特”、“大众”]列为不同品牌,把[“起亚”、“奥迪”]列为了共同品牌。

沙盒:https://jsfiddle.net/zkq9j3Lh/

如果你不反对使用图书馆,http://underscorejs.org/有一种相交方法,可以简化这一点:

var _ = require('underscore');

var target = [ 'apple', 'orange', 'banana'];
var fruit2 = [ 'apple', 'orange', 'mango'];
var fruit3 = [ 'mango', 'lemon', 'pineapple'];
var fruit4 = [ 'orange', 'lemon', 'grapes'];

console.log(_.intersection(target, fruit2)); //returns [apple, orange]
console.log(_.intersection(target, fruit3)); //returns []
console.log(_.intersection(target, fruit4)); //returns [orange]

交集函数将返回一个包含匹配项的新数组,如果不匹配,则返回空数组。

良好的性能解决方案:

我们应该将其中一个数组转换为对象。

const contains = (arr1, mainObj) => arr1.some(el => el in mainObj);
const includes = (arr1, mainObj) => arr1.every(el => el in mainObj);

用法:

const mainList = ["apple", "banana", "orange"];
// We make object from array, you can use your solution to make it
const main = Object.fromEntries(mainList.map(key => [key, true]));

contains(["apple","grape"], main) // => true
contains(["apple","banana","pineapple"], main) // =>  true
contains(["grape", "pineapple"], main) // =>  false

includes(["apple", "grape"], main) // => false
includes(["banana", "apple"], main) // =>  true

您可能会面临由in运算符检查的一些缺点(例如{}//=>true中的“toString”),因此您可以将解决方案更改为obj[key]检查器

console.log("searching Array: "+finding_array);
console.log("searching in:"+reference_array);
var check_match_counter = 0;
for (var j = finding_array.length - 1; j >= 0; j--) 
{
    if(reference_array.indexOf(finding_array[j]) > 0)
    {
        check_match_counter = check_match_counter + 1;
    }
}
 var match = (check_match_counter > 0) ? true : false;
console.log("Final result:"+match);