如何检查数据中是否存在密钥[重复]

Question

大家好，我有以下 zip codes 的数据：

现在我正在尝试执行以下操作。我有输入，我正在写一些邮政编码，我需要检查邮政编码数据中是否存在该邮政编码我应该设置我的状态true如果不存在则false。

这是我的代码：

const zipCode = {
  2101: [
    {
      City: "Boston",
      State: "Massachusetts",
      Delivery: "Yes",
      Address: ""
    }
  ],
  2108: [
    {
      City: "Boston",
      State: "Massachusetts",
      Delivery: "Yes",
      Address: ""
    }
  ],
  2109: [
    {
      City: "Boston",
      State: "Massachusetts",
      Delivery: "Yes",
      Address: ""
    }
  ],
  2110: [
    {
      City: "Boston",
      State: "Massachusetts",
      Delivery: "Yes",
      Address: ""
    }
  ],
  2111: [
    {
      City: "Boston",
      State: "Massachusetts",
      Delivery: "Yes",
      Address: ""
    }
  ],
  2112: [
    {
      City: "Boston",
      State: "Massachusetts",
      Delivery: "Yes",
      Address: ""
    }
  ],
  2113: [
    {
      City: "Boston",
      State: "Massachusetts",
      Delivery: "Yes",
      Address: ""
    }
  ],
 
};

export default zipCode;

    export default function App() {
     const [valid, setValid] = useState(null);
     const [zipCodefromInput, setZipCodeFromInput] = useState();

      const checkZipCode = (e) => {
       setZipCodeFromInput(+e.taget.value);

       Object.keys(zipCode)
        .filter((key) => zipCodefromInput.includes(key))
        .reduce((obj, key) => {
        obj[key] = zipCode[key];
        // setValid(true) else setValid(false) ???
       }, {});
     };

  console.log(valid);

  return (
    <div className="App">
      <input onChange={checkZipCode} />

     
    </div>
  );
}

但这对我不起作用，请帮助我更正我的代码。

Answer 1

当key存在时返回true。

const zipExists = (key) => key in zipCode;

更多信息：Checking if a key exists in a JavaScript object?