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?
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
var target = ["apple","banana","orange"];
var checkArray = ["apple","banana","pineapple"];
var containsOneCommonItem = target.some(x => checkArray.some(y => y === x));`
["apple","grape"] //returns true;
["apple","banana","pineapple"] //returns true;
["grape", "pineapple"] //returns false;
其他回答
使用一些/findIndex和indexOf的组合怎么样?
所以类似这样:
var array1 = ["apple","banana","orange"];
var array2 = ["grape", "pineapple"];
var found = array1.some(function(v) { return array2.indexOf(v) != -1; });
为了使其更可读,可以将此功能添加到Array对象本身。
Array.prototype.indexOfAny = function (array) {
return this.findIndex(function(v) { return array.indexOf(v) != -1; });
}
Array.prototype.containsAny = function (array) {
return this.indexOfAny(array) != -1;
}
注意:如果您想对谓词执行某些操作,可以用另一个findIndex和谓词替换内部indexOf
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:
每
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/
就我个人而言,我会使用以下功能:
var arrayContains = function(array, toMatch) {
var arrayAsString = array.toString();
return (arrayAsString.indexOf(','+toMatch+',') >-1);
}
“toString()”方法将始终使用逗号分隔值。仅适用于基本类型。
这是一个有趣的案例,我认为我应该分享。
假设您有一个对象数组和一个选定过滤器数组。
let arr = [
{ id: 'x', tags: ['foo'] },
{ id: 'y', tags: ['foo', 'bar'] },
{ id: 'z', tags: ['baz'] }
];
const filters = ['foo'];
要将所选过滤器应用于此结构,我们可以
if (filters.length > 0)
arr = arr.filter(obj =>
obj.tags.some(tag => filters.includes(tag))
);
// [
// { id: 'x', tags: ['foo'] },
// { id: 'y', tags: ['foo', 'bar'] }
// ]
ES6溶液:
let arr1 = [1, 2, 3];
let arr2 = [2, 3];
let isFounded = arr1.some( ai => arr2.includes(ai) );
与之不同:必须包含所有值。
let allFounded = arr2.every( ai => arr1.includes(ai) );
希望,会有所帮助。