如何在javascript中使用另一个对象生成多个对象答案

【问题标题】：How to generate the multiple objects using another object in javascript如何在javascript中使用另一个对象生成多个对象
【发布时间】：2017-01-31 10:30:38
【问题描述】：

我有一个这样的对象，

{
    "Distrubutor":"DISTRIBUTOR1",
    "INCLUDE":"INDIA,United States",
    "EXCLUDE":"KARNATAKA-INDIA,CHENNAI-TAMILNADU-INDIA",
    "PARENT-ID":""
}

我想通过使用 Main 对象中的 INCLUDE 属性来生成多个对象，有人可以帮我解决这个问题吗

{
    "parent_id":"",
    "id":"DISTRIBUTOR1",
    "permission":"Granted",
    "country_code":"INDIA"
}

2.  
{
    "parent_id":"",
    "id":"DISTRIBUTOR1",
    "permission":"Granted",
    "country_code":"United States"
}

【问题讨论】：

标签： javascript json node.js lodash

【解决方案1】：

您可以拆分包含的国家并映射新对象。

var data = {"Distrubutor":"DISTRIBUTOR1","INCLUDE":"INDIA,United States","EXCLUDE":"KARNATAKA-INDIA,CHENNAI-TAMILNADU-INDIA","PARENT-ID":""},
    include = data.INCLUDE.split(',').map(function (a) {
        return {
            parent_id: "",
            id: data.Distrubutor,
            permission: "Granted",
            country_code: a                
        };
    });

console.log(include);

.as-console-wrapper { max-height: 100% !important; top: 0; }

【讨论】：

【解决方案2】：

你可以试试这样的：

var obj = {"Distrubutor":"DISTRIBUTOR1","INCLUDE":"INDIA,United States","EXCLUDE":"KARNATAKA-INDIA,CHENNAI-TAMILNADU-INDIA","PARENT-ID":""}

// Keys that does not need to be in returned object
var ignoreKeys = ["EXCLUDE", "INCLUDE"];

var tmp = Object.assign({}, obj)

// Delete all keys that are not required
ignoreKeys.forEach(function(key){ delete tmp[key] })

var result = obj.INCLUDE.split(',').map(function(country){
  return Object.assign({}, tmp, {"country_code": country, "permission": "GRANTED"})
})

console.log(result)

注意：我使用Object.assign复制，但并非所有浏览器都支持。使用前请参考browser compatibility。您也可以参考以下帖子以获取替代方案：What is the most efficient way to deep clone an object in JavaScript?

【讨论】：

【解决方案3】：

这是解决当前问题的另一种方法，也可以回答可能的新问题“你如何使它更复杂”

class PropertyAdapter {
  *populate(target, option){}
}

class DistrubutorAdapter extends PropertyAdapter {
  *populate(target, option){
    target.id = option;
    yield target;
  }
}

class ParentIdAdapter extends PropertyAdapter {
  *populate(target, option){
    target.parent_id = option;
    yield target;
  }  
}

class IncludeAdapter extends PropertyAdapter {
  *populate(target, option){
    option = option.split(/,/g).map(x=>x.trim()).filter(x=>!!x.length);
    for(let v of option){
      let obj = Instantinator.copy(target);
      obj.country_code = v;
      yield obj;
    }
  }  
}

class Instantinator {
  static create(){
    return {permission: 'Granted'};
  }
  
  static copy(src){
    return Object.assign({}, src);
  }
}

const ADAPTERS = new Map();

class ObjectFactory {
  static register(prop, adapter){
    ADAPTERS.set(prop, adapter);
  }
  
  static create(options){
    const pairs = Object.keys(options||{})
      .filter(key => ADAPTERS.has(key))
      .map(key=> ({value: options[key], adapter: ADAPTERS.get(key)}));
    let result = [Instantinator.create()];
    for(let pair of pairs){
      result = result.reduce((prev, cur) => prev.concat([...pair.adapter.populate(cur, pair.value)]), []);
    }
    return result;
  }
}

ObjectFactory.register('Distrubutor', new DistrubutorAdapter());
ObjectFactory.register('PARENT-ID', new ParentIdAdapter());
ObjectFactory.register('INCLUDE', new IncludeAdapter());


var options = {
    "Distrubutor":"DISTRIBUTOR1",
    "INCLUDE":"INDIA,United States",
    "EXCLUDE":"KARNATAKA-INDIA,CHENNAI-TAMILNADU-INDIA",
    "PARENT-ID":""
};

console.log(ObjectFactory.create(options));

.as-console-wrapper { max-height: 100% !important; top: 0; }

【讨论】：