Check If an Array Contains Any Element of Another Array in JavaScript

Check if an array of object is exactly equal to another array that contains one of its property

as @mplungjan mentiond, you can use Every:

let fixed = ["123", "456", "789"];
let variableArray1 = [{
  name: "Joe",
  id: "123"
}, {
  name: "Joe",
  id: "456"
}, {
  name: "Joe",
  id: "789"
}];
let variableArray2 = [{
  name: "Joe",
  id: "123"
}, {
  name: "Joe",
  id: "456"
}, {
  name: "Joe",
  id: "001"
}]

let containsAll1 = variableArray1.every(elem => fixed.includes(elem.id));
let containsAll2 = variableArray2.every(elem => fixed.includes(elem.id));

console.log(containsAll1, containsAll2);

JavaScript: How can i check if an array contains elements in common with a second array?

A quick solution could be something like this:

const pcNumbers = [1,2,3,8,5];
const userNumbers = [1,2,7,8,9];
const newArr = [];

for (let i = 0; i < pcNumbers.length; i++) {
    for (let j = 0; j < userNumbers.length; j++) {
        if (pcNumbers[i] === userNumbers[j]) {
            newArr.push(pcNumbers[i])
        }
    }
};

console.log(`These are in common: ${newArr.join(', ')}`)

This will result in:

These are in common: 1, 2

Determine if one array contains all elements of another array, including any duplicates

const isMultiSubset = (target, value) => {
  const occurences = new Map;
  for(const entry of target) 
    occurences.set(entry, (occurences.get(entry) ?? 0) + 1);

  for(const entry of value)
    if (occurences.has(entry))
       occurences.set(entry, occurences.get(entry) - 1);

  return [...occurences.values()].every(count => count <= 0);   
};

By using a Map to count occurences this can be solved in O(n + m).

Check if an array contains 2 or more elements of another array in JavaScript

Firstly, you can use array#filter combined with array#includes to find all items in arr1 in arr2.

Then check the length of result.

let arr1 = [1, 2, 3];
let arr2 = [2, 3];

let result = arr1.filter(v1 => arr2.includes(v1));
console.log(result.length >= 2);

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