javascript - 对象数组与lodash的深度比较

Question

我有 2 个对象数组，我将与 lodash

进行深入比较

但是，我有一个问题:

> var x = [{a:1, b:2}, {c:3, d:4}];
> var y = [{b:2, a:1}, {d:4, c:3}];
> _.difference(x,y, _.isEqual);
[ { a: 1, b: 2 }, { c: 3, d: 4 } ]

我应该如何比较才能看到两者相等？

Answer 1

您可以使用 differenceWith()用 isEqual()比较器，并调用 isEmpty检查它们是否相等。

var isArrayEqual = function(x, y) {
  return _(x).differenceWith(y, _.isEqual).isEmpty();
};

var result1 = isArrayEqual(
  [{a:1, b:2}, {c:3, d:4}],
  [{b:2, a:1}, {d:4, c:3}]
);

var result2 = isArrayEqual(
  [{a:1, b:2, c: 1}, {c:3, d:4}],
  [{b:2, a:1}, {d:4, c:3}]
);

document.write([
  '<div><label>result1: ', result1, '</label></div>',
  '<div><label>result2: ', result2, '</label></div>',
].join(''));

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.11.2/lodash.js"></script>

2018 年 6 月 22 日更新

此更新是对以下评论的回应:

@ryeballar if any of the array is undefined it returns true. How would you solve this. Thanks in advance buddy

如 differenceWith 文档中所述:

The order and references of result values are determined by the first array.

这意味着只要第一个数组中的所有项都与第二个数组中的所有其他项匹配，则 differenceWith 调用的结果数组将为空。

真正解决问题的另一种解决方案是使用 xorWith()具有与上述解决方案相同的功能链。

var isArrayEqual = function(x, y) {
  return _(x).xorWith(y, _.isEqual).isEmpty();
};

var result1 = isArrayEqual(
  [{a:1, b:2}, {c:3, d:4}],
  [{b:2, a:1}, {d:4, c:3}]
);

var result2 = isArrayEqual(
  [{a:1, b:2, c: 1}, {c:3, d:4}],
  [{b:2, a:1}, {d:4, c:3}]
);

var result3 = isArrayEqual(
  [{a:1, b:2, c: 1}, {c:3, d:4}],
  [{b:2, a:1}, {d:4, c:3}, undefined]
);

console.log('result1:', result1);
console.log('result2:', result2);
console.log('result3:', result3);

.as-console-wrapper{min-height:100%;top:0}

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.10/lodash.min.js"></script>