当您不知道键时访问对象内部的某些内容

Question

我得到以下对象

{
  IuW1zvaSABwH4q: {
    label: 'Random Image of TypeScript not relavent to coworking',
    thumbId: 'd501-f-b601-c8b1-4bd995e',
    schemaType: 'xman-assets-image-set'
  }
}

现在，我想访问其中的thumbID的值，即d501-f-b601-c8b1-4bd995e

但是我的根密钥似乎是动态/随机的（IuW1zvaSABwH4q），如何访问其中的值？

Answer 1

您可以从object获取值，然后访问所需的键。

let obj =  {
    IuW1zvaSABwH4q: 
      {
        label: 'Random Image of TypeScript not relavent to coworking', 
        thumbId: 'd501-f-b601-c8b1-4bd995e',
        schemaType: 'xman-assets-image-set' 
      } 
    }
    
let op = Object.values(obj)[0].thumbId

console.log(op)

Answer 2

您可以使用Array.map它进行转换，并Array.forEach在控制台中进行打印。

const obj = {
    IuW1zvaSABwH4q: {
        label: 'Random Image of TypeScript not relavent to coworking',
        thumbId: 'd501-f-b601-c8b1-4bd995e',
        schemaType: 'xman-assets-image-set'
    },
    YuW1zvaSABwH7q: {
        label: 'Random Image of TypeScript not relavent to coworking',
        thumbId: 'as90-f-b601-c8b1-4bd9958', 
        schemaType: 'xman-assets-image-set'
    }
};
//for one object
console.log(Object.values(obj)[0].thumbId);
//multiple unknown keys
Object.values(obj).map(ele => ele.thumbId).forEach(th=> console.log(th));

Answer 3

假设只有一个属性，则可以通过第一个属性访问它。

const obj = { IuW1zvaSABwH4q: 
      { label: 'Random Image of TypeScript not relavent to coworking', thumbId: 'd501-f-b601-c8b1-4bd995e', schemaType: 'xman-assets-image-set' 
       } 
    };
    
console.log(obj[Object.getOwnPropertyNames(obj)[0]].thumbId);

Answer 4

您可以使用for..in来迭代对象，然后检查该对象是否具有名称键thumbId。如果对象没有thumbId密钥，此检查将确保代码不会引发错误

let obj = {
  IuW1zvaSABwH4q: {
    label: 'Random Image of TypeScript not relavent to coworking',
    thumbId: 'd501-f-b601-c8b1-4bd995e',
    schemaType: 'xman-assets-image-set'
  }
}


for (let keys in obj) {
  if (obj[keys].hasOwnProperty('thumbId')) {
    console.log(obj[keys].thumbId);
  }
}