JavaScript：比较两个对象

Question

I want to compare two objects to make a new object.

original = [
            {id: "A1", name: "Nick", age: 20, country: 'JP', code: 'PHP'}
           ]

edited = [
          {name: "Mike", age: 30, country: 'US'},
          {id: "A1", name: "Nick", age: 25, country: 'US', code: 'PHP'}
         ]

1. Compare two objects ('original' and 'edited')
2. If 'id' is set, compare the same ids' data, and take the data from 'edited', and get ONLY the 'id' and the data that is edited.
3. If 'id' is not set keep the whole data

The final object I want is like below;

final = [
         {name: "Mike", age: 30, country: 'US'},
         {id: "A1", age: 25, country: 'US'}
        ]

I've been trying this using filter, but I can't get desired result...

Answer 1

Try with Array#reduce .

Updated with all key pair match

• Validate the edited array id value is available in original array using Array#map and indexOf function
• If not push entire object to new array
• First recreate the original array to object format like {key:[value]}
• Then match each key value pair match or not with forEach inside the reduce function

 var original = [{id: "A1", name: "Nick", age: 20, country: 'JP'}]; var edited = [{name: "Mike", age: 30, country: 'US'},{id: "A1", name: "Nick", age: 25, country: 'US'}]; var ids_org = Object.keys(original[0]).reduce((a,b,c)=> (a[b]=original.map(a=> a[b]),a),{}); var res = edited.reduce((a, b) => { if (b.id) { Object.keys(b).forEach(i=>{ if(ids_org[i].indexOf(b[i]) > -1 && i != 'id') delete b[i]; }) a.push(b); } else { a.push(b); } return a; }, []); console.log(res)

Answer 2

Here is a function I wrote for comparing objects to their deepest level... the function recursively goes into objects and arrays and pushes every known value to a global components array which is copied into another array for comparing...

 var components = []; var p = { a: 3, b: { a: 1, b: 2, c: 3, d: [1,2,3,4,5] }, c: 3, d: [2,3,4,5,[1,2,3,4], {a: 3, b: 3}, 'hello world'], e: 'jdjdjdk', f: { c: 3, f: function cool() { return 'hello world'; } } } var wow = deep_check_object(p, Object.keys(p)); console.log(wow); components = []; //flattened array can be used for comparing another object function deep_check_object(obj, keys) { keys.forEach((key, index) => { if( typeof(obj[key]) === 'object' && Array.isArray(obj[key]) === false && obj[key] !== null ) { components.push(`${key}-object-${obj[key]}`); push_proto(key, 'object', obj[key]); deep_check_object(obj[key], Object.keys(obj[key])); } else if( typeof(obj[key]) === 'object' && Array.isArray(obj[key]) === true ) { components.push(`${key}-array-${obj[key]}`); push_proto(key, 'array', obj[key]); deep_array_check(key, obj[key]); } else { components.push(`${key}-single-${obj[key]}`); push_proto(key, 'single', obj[key]); } }); return components; } function deep_array_check(key, arr) { for(let i = 0; i < arr.length; i++) { if( typeof(arr[i]) === 'object' && Array.isArray(arr[i]) === false && arr[i] !== null ) { components.push(`${key}-object-${arr[i]}`); push_proto(key, 'object', arr[i]); deep_check_object(arr[i], Object.keys(arr[i])); } else if( typeof(arr[i]) === 'object' && Array.isArray(arr[i]) === true ) { components.push(`${key}-array-${arr[i]}`); push_proto(key, 'array', arr[i]); deep_array_check(key, arr[i]); } else { components.push(`${key}-single-${arr[i]}`); push_proto(key, 'single', arr[i]); } } } function push_proto(k, t, v) { return; //recursively push proto set }

Answer 3

use de structuring to extract out id from the object. use lodash isEqual method to compare and later add back the id to the object.