javascript - 验证对象内的嵌套键[重复]

Posted 2023-02-21

【中文标题】javascript - 验证对象内的嵌套键[重复]

【英文标题】：javascript - validate nested key inside an object [duplicate]

【发布时间】：2021-10-23 12:50:48

【问题描述】：

我有以下 javascript 对象。

let obj = 
  "type": "user",
  "personalDetails": 
    "firstName": "Steven",
    "address": 
      "streetName": "abcd",
      "zipCode": "012345"
    
  ,
  "employeeDetails": 
    "designation": 
      "id": "1234",
      "manage": "Mark",
    
  

如何创建一个动态函数，它将JS object obj 作为 第一个参数，一个父节点作为第二个参数和一个子节点 作为第三个参数。

如果第三个参数作为子节点存在于第二个 参数，函数应该返回true。例如。

const childNodeExist = (obj, personalDetails, firstName) => 
    //.. since firstName exists in personalDetails should return true


const childNodeExist = (obj, employeeDetails, designation) => 
    //.. since designation exists in employeeDetails should return true

const childNodeExist = (obj, employeeDetails, salary) => 
    //.. since salary exists in employeeDetails should return false

【参考方案1】：

你可以试试Object.prototype.hasOwnProperty():

hasOwnProperty() 方法返回一个布尔值，指示对象是否具有指定的属性作为它自己的属性（而不是继承它）。

let obj = 
  "type": "user",
  "personalDetails": 
    "firstName": "Steven",
    "address": 
      "streetName": "abcd",
      "zipCode": "012345"
    
  ,
  "employeeDetails": 
    "designation": 
      "id": "1234",
      "manage": "Mark",
    
  


const childNodeExist = (obj, prop, childProp) => 
    return obj[prop]?.hasOwnProperty(childProp) ?? false; 

console.log(childNodeExist(obj, 'personalDetails', 'firstName'));

console.log(childNodeExist(obj, 'employeeDetails', 'designation'));

console.log(childNodeExist(obj, 'employeeDetails', 'salary'));

更新：支持所有浏览器的替代方式：

let obj = 
  "type": "user",
  "personalDetails": 
    "firstName": "Steven",
    "address": 
      "streetName": "abcd",
      "zipCode": "012345"
    
  ,
  "employeeDetails": 
    "designation": 
      "id": "1234",
      "manage": "Mark",
    
  


const childNodeExist = (obj, prop, childProp) => 
    return obj.hasOwnProperty(prop)? obj[prop].hasOwnProperty(childProp) : false; 

console.log(childNodeExist(obj, 'personalDetails', 'firstName'));

console.log(childNodeExist(obj, 'employeeDetails', 'designation'));

console.log(childNodeExist(obj, 'employeeDetails', 'salary'));

【讨论】：

另一种方式是return Object.keys(obj[prop]).includes(childProp);

@Mamun，可选链接? 可能不适用于所有浏览器，对吧？另一种方式？

@user2281858，在不使用?.的情况下添加了第二个解决方案，请检查:)

【参考方案2】：

这是您需要的吗？

const childNodeExist = (obj, parentNode, childNode) => 
    return (obj[parentNode][childNode] ? true : false);


let obj = 
  "type": "user",
  "personalDetails": 
    "firstName": "Steven",
    "address": 
      "streetName": "abcd",
      "zipCode": "012345"
    
  ,
  "employeeDetails": 
    "designation": 
      "id": "1234",
      "manage": "Mark",
    
  


console.log(childNodeExist(obj, "personalDetails", "firstName"));
console.log(childNodeExist(obj, "employeeDetails", "designation"));
console.log(childNodeExist(obj, "employeeDetails", "salary"));

【参考方案3】：

这样就可以了：

  const childNodeExist = (obj, parentNode, childNode) => Boolean(obj[parentNode][childNode])