js数组取差集

    //数组取差集
    arrDifferenceDet(arr1, arr2) {
      var set1 = new Set(arr1);
      var set2 = new Set(arr2);
      var subset = [];
      for (let item of set1) {
        if (!set2.has(item)) {
          subset.push(item);
        }
      }
      return subset;
    }