How to check if array includes a value from another array in JavaScript
// How to check if array includes a value from another array in JavaScript
const includesAny = (arr, values) => values.some(v => arr.includes(v));
includesAny([1, 2, 3, 4], [2, 9]); // true
includesAny([1, 2, 3, 4], [8, 9]); // false
how to check all elements in array includes in another array javascript
// how to check all elements in array includes in another array javascript
const includesAll = (arr, values) => values.every(v => arr.includes(v));
includesAll([1, 2, 3, 4], [1, 4]); // true
includesAll([1, 2, 3, 4], [1, 5]); // false
let superSet = ['B', 'C', 'A', 'D'];
let subSet = ['D', 'C'];
let mixedSet = new Set([...superSet, ...subSet]);
let isSubset = mixedSet.size == superSet.length
find items in array not in another array javascript
var arr1 = [
{
"prop1": "value1",
"prop2": "value2",
},
{
"prop1": "value3",
"prop2": "value4",
},
{
"prop1": "value5",
"prop2": "value6",
},
];
var arr2 = ['value1','value3', 'newValue'];
// finds all the elements of arr2 that are not in arr1
arr2.filter(
val => !arr1.find( arr1Obj => arr1Obj.prop1 === val)
); // outputs "newValue"