Answers for "diff between two arrays"

diff two arrays javascript

function diffArray(arr1, arr2) {
  return arr1
    .concat(arr2)
    .filter(item => !arr1.includes(item) || !arr2.includes(item));
}

javascript get array difference

function arrayDiff (a1, a2) {
    var a = [], diff = [];
    for (var i = 0; i < a1.length; i++) {
        a[a1[i]] = true;
    }
    for (var i = 0; i < a2.length; i++) {
        if (a[a2[i]]) {
            delete a[a2[i]];
        } else {
            a[a2[i]] = true;
        }
    }
    for (var k in a) {
        diff.push(k);
    }
    return diff;
}
//usage:
console.log(arrayDiff(['red', 'white','green'], [ 'red','white', 'blue']));//["green", "blue"]

Diff Two Arrays

const diffArray = (arr1, arr2) => {
  // Store the different elements
  const diffArray = []
  // Concat both arrays
  const uniqueArr = [...new Set([...arr1, ...arr2])];
  // OR const uniqueArr = [...new Set(arr1.concat(...arr2))]

  // Loop through the unique array and confirm that each element in it
  // is in both arrays(arr1,arr2), else push element not found in both 
  // arrays to the diffArray and return it
  uniqueArr.forEach(elem => {
    if(!arr1.includes(elem) || !arr2.includes(elem))
      diffArray.push(elem)
  })
  return diffArray
}

diffArray([1, 2, 3, 5], [1, 2, 3, 4, 5]);
// With love @kouqhar