我有2个不同的嵌套对象,我需要知道它们是否在其中一个嵌套属性中有不同。

var a = {};
var b = {};

a.prop1 = 2;
a.prop2 = { prop3: 2 };

b.prop1 = 2;
b.prop2 = { prop3: 3 };

对象可以更复杂,有更多嵌套的属性。但这是一个很好的例子。我可以选择使用递归函数或lodash的东西…


当前回答

这段代码返回一个具有不同值的所有属性的对象,以及两个对象的值。对记录差异很有用。

var allkeys = _.union(_.keys(obj1), _.keys(obj2));
var difference = _.reduce(allkeys, function (result, key) {
  if ( !_.isEqual(obj1[key], obj2[key]) ) {
    result[key] = {obj1: obj1[key], obj2: obj2[key]}
  }
  return result;
}, {});

其他回答

如果你需要知道哪些属性是不同的,使用reduce():

_.reduce(a, function(result, value, key) {
    return _.isEqual(value, b[key]) ?
        result : result.concat(key);
}, []);
// → [ "prop2" ]

对于无意中发现这条线索的人,这里有一个更完整的解决方案。它将比较两个对象,并给出所有属性的键,这些属性要么只存在于object1中,要么只存在于object2中,要么同时存在于object1和object2中,但值不同:

/*
 * Compare two objects by reducing an array of keys in obj1, having the
 * keys in obj2 as the intial value of the result. Key points:
 *
 * - All keys of obj2 are initially in the result.
 *
 * - If the loop finds a key (from obj1, remember) not in obj2, it adds
 *   it to the result.
 *
 * - If the loop finds a key that are both in obj1 and obj2, it compares
 *   the value. If it's the same value, the key is removed from the result.
 */
function getObjectDiff(obj1, obj2) {
    const diff = Object.keys(obj1).reduce((result, key) => {
        if (!obj2.hasOwnProperty(key)) {
            result.push(key);
        } else if (_.isEqual(obj1[key], obj2[key])) {
            const resultKeyIndex = result.indexOf(key);
            result.splice(resultKeyIndex, 1);
        }
        return result;
    }, Object.keys(obj2));

    return diff;
}

下面是一个输出示例:

// Test
let obj1 = {
    a: 1,
    b: 2,
    c: { foo: 1, bar: 2},
    d: { baz: 1, bat: 2 }
}

let obj2 = {
    b: 2, 
    c: { foo: 1, bar: 'monkey'}, 
    d: { baz: 1, bat: 2 }
    e: 1
}
getObjectDiff(obj1, obj2)
// ["c", "e", "a"]

如果你不关心嵌套对象并且想要跳过lodash,你可以替换_。isEqual用于正常的值比较,例如obj1[key] === obj2[key]。

要递归地显示一个对象与其他对象的不同之处,可以使用_。Reduce与_结合。isEqual和_.isPlainObject。在这种情况下,你可以比较a与b的不同,或者b与a的不同:

const objectA = { a: { 1: "SAME WILL BE MISSING IN RESULT", 2: "BBB", 3: [1, 2, 3] }, b: "not", c: "foo bar" }; const objectB = { a: { 1: "SAME WILL BE MISSING IN RESULT", 2: [1, 2] }, b: "foo", c: "bar" }; const diff = function(obj1, obj2) { return _.reduce(obj1, function(result, value, key) { if (_.isPlainObject(value)) { result[key] = diff(value, obj2[key]); } else if (!_.isEqual(value, obj2[key])) { result[key] = value; } return result; }, {}); }; const diffAOverB = diff(objectA, objectB); const diffBOverA = diff(objectA, objectB); console.log(diffAOverB); console.log(diffBOverA); <script src="https://cdn.jsdelivr.net/npm/lodash@4.17.4/lodash.min.js"></script>

这是一个简单的带有Lodash深度差异检查器的Typescript,它将生成一个新对象,只包含旧对象和新对象之间的差异。

例如,如果我们有:

const oldData = {a: 1, b: 2};
const newData = {a: 1, b: 3};

结果对象将是:

const result: {b: 3};

它还兼容多层深层对象,对于数组,它可能需要一些调整。

import * as _ from "lodash";

export const objectDeepDiff = (data: object | any, oldData: object | any) => {
  const record: any = {};
  Object.keys(data).forEach((key: string) => {
    // Checks that isn't an object and isn't equal
    if (!(typeof data[key] === "object" && _.isEqual(data[key], oldData[key]))) {
      record[key] = data[key];
    }
    // If is an object, and the object isn't equal
    if ((typeof data[key] === "object" && !_.isEqual(data[key], oldData[key]))) {
      record[key] = objectDeepDiff(data[key], oldData[key]);
    }
  });
  return record;
};

已经有很多答案发布,但对于那些好奇的人来说,避免编写任何代码来计算具有任何类型结构的两个对象之间的差异,实际上有一个库可以做到这一点。Lodash isEqual只返回true或false,它不返回任何关于更改属性的信息。https://www.npmjs.com/package/deep-diff

它返回两个对象之间差异的完整细节

import DeepDiff from 'deep-diff';
let a = {...} //some object
let b = {...} //some object 
var differences = DeepDiff.diff(a, b);

在这篇文章中也有人提出了类似的问题 获取2个JSON对象之间的差异