我有两个对象:oldObj和newObj。

oldObj中的数据用于填充表单,而newObj是用户更改该表单中的数据并提交的结果。

这两个物体都很深。它们具有对象或对象数组等属性-它们可以有n层深,因此diff算法需要递归。

现在我不仅需要弄清楚从oldObj到newObj更改了什么(如添加/更新/删除),而且还需要知道如何最好地表示它。

到目前为止,我的想法只是构建一个通用的deepdiffbetweenobjects方法,该方法将返回窗体上的对象{add:{…},upd:{…},del:{…但我转念一想:以前一定有人需要它。

所以…有没有人知道一个库或一段代码可以做到这一点,并且可能有更好的方式来表示差异(以一种仍然是JSON可序列化的方式)?

更新:

我想到了一个更好的方法来表示更新的数据,通过使用与newObj相同的对象结构,但将所有属性值转换为窗体上的对象:

{type: '<update|create|delete>', data: <propertyValue>}

如果newObj。prop1 = 'new value'和oldObj。prop1 = 'old value'它将设置returnbj。Prop1 = {type: 'update', data: 'new value'}

更新2:

当我们处理数组的属性时,它会变得非常麻烦,因为数组[1,2,3]应该被计算为等于[2,3,1],这对于基于值的类型的数组(如string, int和bool)来说足够简单,但是当涉及到引用类型的数组(如对象和数组)时就很难处理了。

数组的示例应该是相等的:

[1,[{c: 1},2,3],{a:'hey'}] and [{a:'hey'},1,[3,{c: 1},2]]

不仅要检查这种类型的深度值相等相当复杂,而且要找出一种表示可能发生的变化的好方法。


当前回答

const diff = require("deep-object-diff").diff;
let differences = diff(obj2, obj1);

有一个每周下载量超过50万的npm模块:https://www.npmjs.com/package/deep-object-diff

我喜欢对象式的差异表示-特别是当它形成时,很容易看到结构。

const diff = require("deep-object-diff").diff;

const lhs = {
  foo: {
    bar: {
      a: ['a', 'b'],
      b: 2,
      c: ['x', 'y'],
      e: 100 // deleted
    }
  },
  buzz: 'world'
};

const rhs = {
  foo: {
    bar: {
      a: ['a'], // index 1 ('b')  deleted
      b: 2, // unchanged
      c: ['x', 'y', 'z'], // 'z' added
      d: 'Hello, world!' // added
    }
  },
  buzz: 'fizz' // updated
};

console.log(diff(lhs, rhs)); // =>
/*
{
  foo: {
    bar: {
      a: {
        '1': undefined
      },
      c: {
        '2': 'z'
      },
      d: 'Hello, world!',
      e: undefined
    }
  },
  buzz: 'fizz'
}
*/

其他回答

从sbgoran的答案中得到扩展和简化的函数。 这允许深度扫描和发现数组的相似性。

var result = objectDifference({ a:'i am unchanged', b:'i am deleted', e: {a: 1,b:false, c: null}, f: [1,{a: 'same',b:[{a:'same'},{d: 'delete'}]}], g: new Date('2017.11.25'), h: [1,2,3,4,5] }, { a:'i am unchanged', c:'i am created', e: {a: '1', b: '', d:'created'}, f: [{a: 'same',b:[{a:'same'},{c: 'create'}]},1], g: new Date('2017.11.25'), h: [4,5,6,7,8] }); console.log(result); function objectDifference(obj1, obj2){ if((dataType(obj1) !== 'array' && dataType(obj1) !== 'object') || (dataType(obj2) !== 'array' && dataType(obj2) !== 'object')){ var type = ''; if(obj1 === obj2 || (dataType(obj1) === 'date' && dataType(obj2) === 'date' && obj1.getTime() === obj2.getTime())) type = 'unchanged'; else if(dataType(obj1) === 'undefined') type = 'created'; if(dataType(obj2) === 'undefined') type = 'deleted'; else if(type === '') type = 'updated'; return { type: type, data:(obj1 === undefined) ? obj2 : obj1 }; } if(dataType(obj1) === 'array' && dataType(obj2) === 'array'){ var diff = []; obj1.sort(); obj2.sort(); for(var i = 0; i < obj2.length; i++){ var type = obj1.indexOf(obj2[i]) === -1?'created':'unchanged'; if(type === 'created' && (dataType(obj2[i]) === 'array' || dataType(obj2[i]) === 'object')){ diff.push( objectDifference(obj1[i], obj2[i]) ); continue; } diff.push({ type: type, data: obj2[i] }); } for(var i = 0; i < obj1.length; i++){ if(obj2.indexOf(obj1[i]) !== -1 || dataType(obj1[i]) === 'array' || dataType(obj1[i]) === 'object') continue; diff.push({ type: 'deleted', data: obj1[i] }); } } else { var diff = {}; var key = Object.keys(obj1); for(var i = 0; i < key.length; i++){ var value2 = undefined; if(dataType(obj2[key[i]]) !== 'undefined') value2 = obj2[key[i]]; diff[key[i]] = objectDifference(obj1[key[i]], value2); } var key = Object.keys(obj2); for(var i = 0; i < key.length; i++){ if(dataType(diff[key[i]]) !== 'undefined') continue; diff[key[i]] = objectDifference(undefined, obj2[key[i]]); } } return diff; } function dataType(data){ if(data === undefined || data === null) return 'undefined'; if(data.constructor === String) return 'string'; if(data.constructor === Array) return 'array'; if(data.constructor === Object) return 'object'; if(data.constructor === Number) return 'number'; if(data.constructor === Boolean) return 'boolean'; if(data.constructor === Function) return 'function'; if(data.constructor === Date) return 'date'; if(data.constructor === RegExp) return 'regex'; return 'unknown'; }

我在这里跌跌撞撞地试图寻找一种方法来区分两个对象之间的区别。这是我使用Lodash的解决方案:

// Get updated values (including new values)
var updatedValuesIncl = _.omitBy(curr, (value, key) => _.isEqual(last[key], value));

// Get updated values (excluding new values)
var updatedValuesExcl = _.omitBy(curr, (value, key) => (!_.has(last, key) || _.isEqual(last[key], value)));

// Get old values (by using updated values)
var oldValues = Object.keys(updatedValuesIncl).reduce((acc, key) => { acc[key] = last[key]; return acc; }, {});

// Get newly added values
var newCreatedValues = _.omitBy(curr, (value, key) => _.has(last, key));

// Get removed values
var deletedValues = _.omitBy(last, (value, key) => _.has(curr, key));

// Then you can group them however you want with the result

Code snippet below: var last = { "authed": true, "inForeground": true, "goodConnection": false, "inExecutionMode": false, "online": true, "array": [1, 2, 3], "deep": { "nested": "value", }, "removed": "value", }; var curr = { "authed": true, "inForeground": true, "deep": { "nested": "changed", }, "array": [1, 2, 4], "goodConnection": true, "inExecutionMode": false, "online": false, "new": "value" }; // Get updated values (including new values) var updatedValuesIncl = _.omitBy(curr, (value, key) => _.isEqual(last[key], value)); // Get updated values (excluding new values) var updatedValuesExcl = _.omitBy(curr, (value, key) => (!_.has(last, key) || _.isEqual(last[key], value))); // Get old values (by using updated values) var oldValues = Object.keys(updatedValuesIncl).reduce((acc, key) => { acc[key] = last[key]; return acc; }, {}); // Get newly added values var newCreatedValues = _.omitBy(curr, (value, key) => _.has(last, key)); // Get removed values var deletedValues = _.omitBy(last, (value, key) => _.has(curr, key)); console.log('oldValues', JSON.stringify(oldValues)); console.log('updatedValuesIncl', JSON.stringify(updatedValuesIncl)); console.log('updatedValuesExcl', JSON.stringify(updatedValuesExcl)); console.log('newCreatedValues', JSON.stringify(newCreatedValues)); console.log('deletedValues', JSON.stringify(deletedValues)); <script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.15/lodash.js"></script>

这只会返回属性改变的新对象。(省略和isEmpty是lodash中的函数)

export const getObjectDifference = <T extends {}>(originalObject: T, newObject: T) => {
const sameProperties: string[] = [];

Object.entries(originalObject).forEach(original => {
    Object.entries(newObject).forEach(newObj => {
        if (original[0] === newObj[0]) {
            if (original[1] === newObj[1])
                sameProperties.push(newObj[0]);
        }
    });
});

const objectDifference: T = omit(newObject, sameProperties) as T;
if (isEmpty(objectDifference))
    return null;
else
    return objectDifference; }

我写了一个小类来做你想做的,你可以在这里测试。

唯一不同于你的建议的是我不考虑

[1,[{c: 1},2,3],{a:'hey'}]

and

[{a:'hey'},1,[3,{c: 1},2]]

相等,因为我认为数组中元素的顺序不相等。当然,如果需要,这可以改变。此外,这段代码还可以进一步增强,将函数作为参数,用于基于传递的原语值以任意方式格式化diff对象(现在这项工作由"compareValues"方法完成)。

var deepDiffMapper = function () { return { VALUE_CREATED: 'created', VALUE_UPDATED: 'updated', VALUE_DELETED: 'deleted', VALUE_UNCHANGED: 'unchanged', map: function(obj1, obj2) { if (this.isFunction(obj1) || this.isFunction(obj2)) { throw 'Invalid argument. Function given, object expected.'; } if (this.isValue(obj1) || this.isValue(obj2)) { return { type: this.compareValues(obj1, obj2), data: obj1 === undefined ? obj2 : obj1 }; } var diff = {}; for (var key in obj1) { if (this.isFunction(obj1[key])) { continue; } var value2 = undefined; if (obj2[key] !== undefined) { value2 = obj2[key]; } diff[key] = this.map(obj1[key], value2); } for (var key in obj2) { if (this.isFunction(obj2[key]) || diff[key] !== undefined) { continue; } diff[key] = this.map(undefined, obj2[key]); } return diff; }, compareValues: function (value1, value2) { if (value1 === value2) { return this.VALUE_UNCHANGED; } if (this.isDate(value1) && this.isDate(value2) && value1.getTime() === value2.getTime()) { return this.VALUE_UNCHANGED; } if (value1 === undefined) { return this.VALUE_CREATED; } if (value2 === undefined) { return this.VALUE_DELETED; } return this.VALUE_UPDATED; }, isFunction: function (x) { return Object.prototype.toString.call(x) === '[object Function]'; }, isArray: function (x) { return Object.prototype.toString.call(x) === '[object Array]'; }, isDate: function (x) { return Object.prototype.toString.call(x) === '[object Date]'; }, isObject: function (x) { return Object.prototype.toString.call(x) === '[object Object]'; }, isValue: function (x) { return !this.isObject(x) && !this.isArray(x); } } }(); var result = deepDiffMapper.map({ a: 'i am unchanged', b: 'i am deleted', e: { a: 1, b: false, c: null }, f: [1, { a: 'same', b: [{ a: 'same' }, { d: 'delete' }] }], g: new Date('2017.11.25') }, { a: 'i am unchanged', c: 'i am created', e: { a: '1', b: '', d: 'created' }, f: [{ a: 'same', b: [{ a: 'same' }, { c: 'create' }] }, 1], g: new Date('2017.11.25') }); console.log(result);

这将把[1,2,3]和[3,2,1]视为相等(deep object) 因为我需要把它们之间的区别形象化:

[
  {
    "a":1,
    "b":1
  },
  {
    "a":1,
    "b":1
  }
]

and

[
  {
    "a":1,
    "b":1
  },
  {
    "a":"OH NO",
    "b":"an insertion"
  },
  {
    "a":1,
    "b":1
  }
]

所以我想看看它们的碰撞,这是剩下的:

[]
and
[
  {
    "a":"OH NO",
    "b":"an insertion"
  }
]

在我看来,这是最好的表现方式。 {添加:{…},乌利希期刊指南:{…},德尔:{…}}很难读懂


我提供了2个函数:objectcollision (obj1,obj2)和arraycollision (arr1,arr2)

console.log(ArrayCollide([1,2,3],[3,2,1]))
// false
//everything collided -> false
console.log(ArrayCollide([1],[2,1]))
// [ [], [ 2 ] ]
//1 and 1 collided, even if they are on different indices

//array of objects
const arr1 = 
[
  {
    "a":1,
    "b":1
  },
  {
    "a":1,
    "b":1
  }
]
const arr2 = 
[
  {
    "a":1,
    "b":1
  },
  {
    "a":"OH NO",
    "b":"an insertion"
  },
  {
    "a":1,
    "b":1
  }
]
const newArrays = ArrayCollide(arr1, arr2)
console.log(newArrays[0])
console.log(newArrays[1])
console.log('\n')
// []
// [ { a: 'OH NO', b: 'an insertion' } ]
// everything collided until this is left

//ObjectCollide
const obj1 = { a: '111', c: { q: 'no', a: '333' } }
const obj2 = { a: '111', p: 'ok', c: { a: '333' } }
ObjectCollide(obj1, obj2) //in place
console.log(obj1)
console.log(obj2)
console.log('\n')
// { c: { q: 'no' } }
// { p: 'ok', c: {} }
// obj["a"] collided and obj["c"]["a"] collided

//testing empty array
const a1 = { a: [] }
const a2 = { a: [], b: '2' }
ObjectCollide(a1, a2) //in place
console.log(a1)
console.log(a2)
console.log('\n')
// {}
// { b: '2' }
// obj["a"] collided

//DIFFERENT TYPES
const b1 = {a:true}
const b2 = {a:[1,2]}
ObjectCollide(b1,b2) //in place
console.log(b1)
console.log(b2)
// { a: true }
// { a: [ 1, 2 ] }

function ObjectCollide(obj1, obj2) {
  //in place, returns true if same

  // delete same
  const keys = Object.keys(obj1)
  const len = keys.length
  let howManyDeleted = 0
  for (let i = 0; i < len; i++) {
    const key = keys[i]

    const type1 = Array.isArray(obj1[key]) === true ? 'array' : typeof obj1[key]
    const type2 = Array.isArray(obj2[key]) === true ? 'array' : typeof obj2[key]
    if (type1!==type2) {
      continue
    }
    switch (type1) {
      case 'object':
        if (ObjectCollide(obj1[key], obj2[key])) {
          delete obj1[key]
          delete obj2[key]
          howManyDeleted++
        }
        continue
      case 'array':
        const newArrays = ArrayCollide(obj1[key], obj2[key])
        if (newArrays) {
          obj1[key] = newArrays[0]
          obj2[key] = newArrays[1]
        } else {
          delete obj1[key]
          delete obj2[key]
          howManyDeleted++
        }
        continue
      default:
        //string, number, I hope it covers everything else
        if (obj1[key] === obj2[key]) {
          delete obj1[key]
          delete obj2[key]
          howManyDeleted++
        }
    }
  }


  if (howManyDeleted === len && Object.keys(obj2).length === 0) {
    // return 'delete the stuff'
    // same. we've deleted everything!
    return true
  }

}
function ArrayCollide(arr1, arr2) {
  // returns [newArr1, newArr2] or false if same arrays (ignore order)
  const stringifyObj = {}

  const newArr1 = []
  const newArr2 = []
  for (let i = 0, len = arr1.length; i < len; i++) {
    const value = arr1[i]
    const stringified = JSON.stringify(value)
    stringifyObj[stringified]
    // arr = [count, ...]
    const arr = stringifyObj[stringified] || (stringifyObj[stringified] = [0])
    arr[0]++
    arr.push(value)
  }
  //in 2 but not in 1
  for (let i = 0, len = arr2.length; i < len; i++) {
    const value = arr2[i]
    const stringified = JSON.stringify(value)
    const arr = stringifyObj[stringified]
    if (arr === undefined) {
      newArr2.push(value)
    } else {
      if (arr[0] === 0) {
        newArr2.push(value)
      } else {
        arr[0]--
      }
    }
  }
  //in 1 but not in 2
  stringifyKeys = Object.keys(stringifyObj)
  for (let i = 0, len = stringifyKeys.length; i < len; i++) {
    const arr = stringifyObj[stringifyKeys[i]]

    for (let i = 1, len = arr[0] + 1; i < len; i++) {
      newArr1.push(arr[i])
    }
  }
  if (newArr1.length || newArr2.length) {
    return [newArr1, newArr2]
  } else {
    return false
  }

}

我想解决的问题是:

JSON文件不断重新排序,我想恢复JSON,如果它是等效的:像{a:1,b:2}和{b:2,a:1} 但是因为我不相信我的代码(我犯了一个错误),我想看到diff并自己检查它,我可以Ctrl+F到原始文件使用这个diff。