javascript - 减少条件未定义的返回

Question

我有一个解析为 JSON 对象的字符串。现在我想检查每个对象键是否包含某个子字符串。在这种情况下，我想将其添加到我累积的对象中。不知怎的，我总是变得不确定。

代码如下:

const myString = '{ "Address__c": "3QAO", "Id": "OxWQAU", "Address__r": { "Address_Line_1__c": "kjj", "Address_Line_2__c": "kl", "Country__c": "United States", "State__c": "California", "Id": "a022M00001aJIW3QAO", "CountryLabel": "United States", "StateLabel": "California" } }';

const parsed = JSON.parse(myString);
const nameSpace = 'NameSpace__';

const newObj = Object.keys(parsed).reduce((acc,curr) => {

    if(curr.includes('__c')){
        return {...acc , [nameSpace + curr] : parsed[curr]};
    }


},{})

console.log(newObj)

编辑:

因此添加 else 会得到以下结果:

{ NameSpace__Address__c: '3QAO' }

怎么可能只修改一个键呢。当超过 1 个包含此 '__c' 字符串时

Answer 1

除了添加 else { return acc } 之外，您的结果仅包含单个键是有原因的。

您的已解析对象是:

{ Address__c: '3QAO',
  Id: 'OxWQAU',
  Address__r: 
   { Address_Line_1__c: 'kjj',
     Address_Line_2__c: 'kl',
     Country__c: 'United States',
     State__c: 'California',
     Id: 'a022M00001aJIW3QAO',
     CountryLabel: 'United States',
     StateLabel: 'California' } }

这意味着Object.keys(parsed)是:

[ 'Address__c', 'Id', 'Address__r' ]

所以这些是您可能的 curr 值。

如果您也想添加嵌套键，则可以使用递归方法，或者预先展平结构。

不干净的递归解决方案看起来像:

const myString = '{ "Address__c": "3QAO", "Id": "OxWQAU", "Address__r": { "Address_Line_1__c": "kjj", "Address_Line_2__c": "kl", "Country__c": "United States", "State__c": "California", "Id": "a022M00001aJIW3QAO", "CountryLabel": "United States", "StateLabel": "California" } }';

const parsed = JSON.parse(myString);
const nameSpace = 'NameSpace__';

const newObj = parsed => Object.keys(parsed).reduce((acc,curr) => {

    if (parsed[curr] instanceof Object) {
      return {...acc, ...newObj(parsed[curr])}
    }
    
    if(curr.includes('__c')) {
        return {...acc , [nameSpace + curr] : parsed[curr]};
    } else {
      return acc;
    }

},{})

console.log("result: ", newObj(parsed))