使用不同的键但是具有相同的值合并两个无序对象？

Question

合并obj1和obj2等对象以在javascript中获取obj3。

obj1 = [{fruit: 'watermelon', sweetness: 3},{fruit: 'banana', sweetness: 4},{fruit: 'apple', sweetness: 5}] 
obj2 = [{fruit_name: 'apple', color: 'red'},{fruit_name: 'banana', color:'yellow'},{fruit_name: 'watermelon', color:'green'}] 

obj3 = [{fruit_name: 'apple', color: 'red', sweetness: 5},{fruit_name: 'banana', color:'yellow', sweetness: 4},{fruit_name: 'watermelon', color:'green', sweetness: 3}] 

Answer 1

可以第一通过合并创建hashtable类似对象使用#forEach然后分机RACT使用#map()功能所需的阵列 - 看演示如下：

var obj1 = [{fruit: 'watermelon', sweetness: 3},{fruit: 'banana', sweetness: 4},{fruit: 'apple', sweetness: 5}], 
 
    obj2 = [{fruit_name: 'apple', color: 'red'},{fruit_name: 'banana', color:'yellow'},{fruit_name: 'watermelon', color:'green'}], hash = {}; 
 

 
// function to create a hashtable 
 
function classify(e) { 
 
    if(hash[e.fruit] || hash[e.fruit_name]) { 
 
    Object.keys(e).forEach(function(c){ 
 
     hash[e.fruit || e.fruit_name][c] = e[c]; 
 
    }); 
 
    } else { 
 
    hash[e.fruit_name || e.fruit] = e; 
 
    } 
 
} 
 

 
// add to hash 
 
obj1.forEach(classify); 
 
obj2.forEach(classify); 
 

 
// extract the result 
 
var obj3 = Object.keys(hash).map(function(e){ 
 
    delete hash[e]['fruit']; 
 
    return hash[e]; 
 
}); 
 

 
console.log(obj3);

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Answer 2

您的数据结构不正确。你不能在数组中保存“'水果：'西瓜'”（键，值对）。

它将给出一个错误：Uncaught SyntaxError: Unexpected token :

我假设你正在尝试做的是：

obj1 = [{fruit: 'watermelon', sweetness: 3},{fruit: 'banana', sweetness: 4},{fruit: 'apple', sweetness: 5}] 
 
    obj2 = [{fruit_name: 'apple', color: 'red'},{fruit_name: 'banana', color:'yellow'},{fruit_name: 'watermelon', color:'green'}] 
 
    obj3 = []; 
 
    
 
for (i = 0; i < obj1.length; i++) { 
 
    for (j = 0; j < obj2.length; j++) { 
 
    if (obj1[i].fruit === obj2[j].fruit_name) { 
 
     var temp = { 
 
     fruit_name: obj2[j].fruit_name, 
 
     color: obj2[j].color, 
 
     sweetness: obj1[i].sweetness 
 
     } 
 
     obj3.push(temp); 
 
    } 
 
    } 
 
} 
 

 
console.log(obj3);

Answer 3

let obj1 = [{fruit: 'watermelon', sweetness: 3},{fruit: 'banana', sweetness: 4},{fruit: 'apple', sweetness: 5}]; 
let obj2 = [{fruit_name: 'apple', color: 'red'},{fruit_name: 'banana', color:'yellow'},{fruit_name: 'watermelon', color:'green'}]; 

function regulate(a) { 
    return a.map(v => { 
    if (v.fruit) { 
     v.fruit_name = v.fruit; 
     delete v.fruit; 
    } 
    return v; 
    }); 
} 


let a = [].concat(regulate(obj1), regulate(obj2)); 

let merged = []; 
a.reduce((m, v) => { 
    let f = m.filter(v2 => v2.fruit_name === v.fruit_name); 
    if (f.length > 0) { 
    Object.assign(f[0], v); 
    } else { 
    m.push(v); 
    } 
    return m; 
}, merged); 

console.log(merged); 

Answer 4

这是相当简单的放在一起的通用功能合并对象的两个阵列使用共享密钥。最简单的方法是使用基于关联数组的映射，如下所示。请注意，您可以使用此例程解决类似类型的任何问题，但它绝对适用于您的数据 - 请参阅最后链接的JSFiddle。

（ETA：共享密钥只加一次，与作为KEY1提供的名称;如果希望第二键在输出卷起，只需交换对函数的自变量）

obj1 = [{fruit: 'watermelon', sweetness: 3},{fruit: 'banana', sweetness: 4},{fruit: 'apple', sweetness: 5}]; 
obj2 = [{fruit_name: 'apple', color: 'red'},{fruit_name: 'banana', color:'yellow'},{fruit_name: 'watermelon', color:'green'}]; 

function mergeObjectArrays(array1, key1, array2, key2) { 
    var map = []; // an associative array/hashtable 
    var arrayValue, mapValue, propertyNames, propertyName, propertyValue; 

    // 1. Loop over one array, populating the map by each object's specified key 
    for(var x = 0; x < array1.length; x++) { 
    array1Value = array1[x]; 
    map[array1Value[key1]] = array1Value; 
    map.push(array1Value); 
    } 

    // 2. Loop over the other array, matching on the provided keys 
    for(var x = 0; x < array2.length; x++) { 
    arrayValue = array2[x]; 
    mapValue = map[arrayValue[key2]]; 

    if (typeof(mapValue) != 'undefined') { // add all missing non-keyed properties to the mapped/merged object 
     propertyNames = Object.keys(arrayValue); 
     for (var y = 0; y < propertyNames.length; y++) { 
      propertyName = propertyNames[y]; 
      if (propertyName != key1 && propertyName != key2) { // .. as that shared value is already added 
      propertyValue = arrayValue[propertyName]; 
      mapValue[propertyName] = propertyValue; 
      } 
     }  
    } 
    else { // it's missing from the mapping, so at least add it though it will be missing array1 data 
     map[arrayValue[key2]] = arrayValue; 
     map.push(arrayValue); 
    } 
    } 

    return map; 
} 

var mergedArrays = mergeObjectArrays(obj1, 'fruit', obj2, 'fruit_name'); 

Here's a working sample.

Answer 5

不是一般的解决方案，但足以让你的情况：

var obj1 = [{fruit: 'watermelon', sweetness: 3},{fruit: 'banana', sweetness: 4},{fruit: 'apple', sweetness: 5}] 
 
var obj2 = [{fruit_name: 'apple', color: 'red'},{fruit_name: 'banana', color:'yellow'},{fruit_name: 'watermelon', color:'green'}] 
 

 
var obj3 = obj2.map(o => Object.assign({}, o, {'sweetness': obj1.find(p => p.fruit === o.fruit_name).sweetness})) 
 

 
console.log(obj3)