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

如今,有相当多的模块可用于此。我最近写了一个模块来做到这一点,因为我不满意我发现的大量不同的模块。它被称为odiff: https://github.com/Tixit/odiff。我还列出了一些最流行的模块,以及为什么它们不能在odiff的自述中被接受,如果odiff没有你想要的属性,你可以查看一下。这里有一个例子:

var a = [{a:1,b:2,c:3},              {x:1,y: 2, z:3},              {w:9,q:8,r:7}]
var b = [{a:1,b:2,c:3},{t:4,y:5,u:6},{x:1,y:'3',z:3},{t:9,y:9,u:9},{w:9,q:8,r:7}]

var diffs = odiff(a,b)

/* diffs now contains:
[{type: 'add', path:[], index: 2, vals: [{t:9,y:9,u:9}]},
 {type: 'set', path:[1,'y'], val: '3'},
 {type: 'add', path:[], index: 1, vals: [{t:4,y:5,u:6}]}
]
*/

其他回答

我已经使用这段代码来完成你所描述的任务:

function mergeRecursive(obj1, obj2) {
    for (var p in obj2) {
        try {
            if(obj2[p].constructor == Object) {
                obj1[p] = mergeRecursive(obj1[p], obj2[p]);
            }
            // Property in destination object set; update its value.
            else if (Ext.isArray(obj2[p])) {
                // obj1[p] = [];
                if (obj2[p].length < 1) {
                    obj1[p] = obj2[p];
                }
                else {
                    obj1[p] = mergeRecursive(obj1[p], obj2[p]);
                }

            }else{
                obj1[p] = obj2[p];
            }
        } catch (e) {
            // Property in destination object not set; create it and set its value.
            obj1[p] = obj2[p];
        }
    }
    return obj1;
}

这将为您提供一个新对象,该对象将合并窗体中的旧对象和新对象之间的所有更改

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);

下面是一个JavaScript库,可以用来查找两个JavaScript对象之间的差异:

Github URL: https://github.com/cosmicanant/recursive-diff

npm捷的url:北京方位www.npmjs.犯下/ recursiff

递归-diff库可以在浏览器中使用,也可以在基于Node.js的服务器端应用程序中使用。对于浏览器,它可以使用如下:

<script type="text" src="https://unpkg.com/recursive-diff@latest/dist/recursive-diff.min.js"/>
<script type="text/javascript">
     const ob1 = {a:1, b: [2,3]};
     const ob2 = {a:2, b: [3,3,1]};
     const delta = recursiveDiff.getDiff(ob1,ob2); 
     /* console.log(delta) will dump following data 
     [
         {path: ['a'], op: 'update', val: 2}
         {path: ['b', '0'], op: 'update',val: 3},
         {path: ['b',2], op: 'add', val: 1 },
     ]
      */
     const ob3 = recursiveDiff.applyDiff(ob1, delta); //expect ob3 is deep equal to ob2
 </script>

而在一个基于node.js的应用程序中,它可以这样使用:

const diff = require('recursive-diff');
const ob1 = {a: 1}, ob2: {b:2};
const diff = diff.getDiff(ob1, ob2);

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>

我已经为我的一个项目写了一个函数,它将对象作为用户选项与其内部克隆进行比较。 它还可以验证,甚至替换默认值,如果用户输入坏类型的数据或删除,在纯javascript。

在IE8中100%有效。测试成功。

//  ObjectKey: ["DataType, DefaultValue"]
reference = { 
    a : ["string", 'Defaul value for "a"'],
    b : ["number", 300],
    c : ["boolean", true],
    d : {
        da : ["boolean", true],
        db : ["string", 'Defaul value for "db"'],
        dc : {
            dca : ["number", 200],
            dcb : ["string", 'Default value for "dcb"'],
            dcc : ["number", 500],
            dcd : ["boolean", true]
      },
      dce : ["string", 'Default value for "dce"'],
    },
    e : ["number", 200],
    f : ["boolean", 0],
    g : ["", 'This is an internal extra parameter']
};

userOptions = { 
    a : 999, //Only string allowed
  //b : ["number", 400], //User missed this parameter
    c: "Hi", //Only lower case or case insitive in quotes true/false allowed.
    d : {
        da : false,
        db : "HelloWorld",
        dc : {
            dca : 10,
            dcb : "My String", //Space is not allowed for ID attr
            dcc: "3thString", //Should not start with numbers
            dcd : false
      },
      dce: "ANOTHER STRING",
    },
    e: 40,
    f: true,
};


function compare(ref, obj) {

    var validation = {
        number: function (defaultValue, userValue) {
          if(/^[0-9]+$/.test(userValue))
            return userValue;
          else return defaultValue;
        },
        string: function (defaultValue, userValue) {
          if(/^[a-z][a-z0-9-_.:]{1,51}[^-_.:]$/i.test(userValue)) //This Regex is validating HTML tag "ID" attributes
            return userValue;
          else return defaultValue;
        },
        boolean: function (defaultValue, userValue) {
          if (typeof userValue === 'boolean')
            return userValue;
          else return defaultValue;
        }
    };

    for (var key in ref)
        if (obj[key] && obj[key].constructor && obj[key].constructor === Object)
          ref[key] = compare(ref[key], obj[key]);
        else if(obj.hasOwnProperty(key))
          ref[key] = validation[ref[key][0]](ref[key][1], obj[key]); //or without validation on user enties => ref[key] = obj[key]
        else ref[key] = ref[key][1];
    return ref;
}

//console.log(
    alert(JSON.stringify( compare(reference, userOptions),null,2 ))
//);

/ *结果

{
  "a": "Defaul value for \"a\"",
  "b": 300,
  "c": true,
  "d": {
    "da": false,
    "db": "Defaul value for \"db\"",
    "dc": {
      "dca": 10,
      "dcb": "Default value for \"dcb\"",
      "dcc": 500,
      "dcd": false
    },
    "dce": "Default value for \"dce\""
  },
  "e": 40,
  "f": true,
  "g": "This is an internal extra parameter"
}

*/