Question

从下方JSON获取“ Root_Zones” 值的最佳方法是什么？

例如，如果我想要“全名”，那么我就这样做：

UserConnectResponse.Result_Data.Full_Name,

但是如果我想要Root_Zones，Successor_Zones，Water_Source_Groups，那么我如何得到它们？因为我做的因为它给null！

这是功能逻辑：

const saveDbData = async (data) => {
  console.log('THE JSON DATA IS:', JSON.stringify(data) + ' ' + 'ROWS');
  const UserConnectResponse = data;
  await insertUserConnectResponseData(
    UserConnectResponse.Req_Type,
    UserConnectResponse.Language_Code,
    UserConnectResponse.User_ID,
    UserConnectResponse.Session_ID,
    UserConnectResponse.Session_Key,
    UserConnectResponse.Client_Type,
    UserConnectResponse.Result_Code,
    UserConnectResponse.Result_Message,
    UserConnectResponse.Result_Data.Full_Name,
    UserConnectResponse.Result_Data.Root_Zones,
    UserConnectResponse.Result_Data.Successor_Zones,
    UserConnectResponse.Result_Data.Water_Source_Groups
  )
    .catch((err) => console.log('ERROR AFTER INSERT:', err))
    .then((result) => console.log('RESULT AFTER INSERT:', data, result));

  const fetchawesome = await fetchUserConnectResponseData();
  console.log('tblUserConnectResponseData AFTER INSERT IS: :', fetchawesome);
};

这是JSON

{
  "Req_Type": "string",
  "Language_Code": "string",
  "User_ID": "string",
  "Session_ID": "string",
  "Session_Key": "string",
  "Client_Type": "string",
  "Result_Code": 0,
  "Result_Message": "string",
  "Result_Data": {
    "Full_Name": "string",
    "Root_Zones": [
      {
        "Zone_ID": 0,
        "Zone_Name": "string"
      }
    ],
    "Successor_Zones": [
      {
        "Zone_ID": 0,
        "Zone_Name": "string"
      }
    ],
    "Water_Source_Groups": [
      {
        "Group_ID": 0,
        "Group_Name": "string",
        "Zone_ID": 0
      }
    ]
  },
  "AccessDenied": "string"
}

Answer 1

使用destructuring作为默认值，或者使用optional chaining operator。

const data = {
  Req_Type: "string",
  Language_Code: "string",
  User_ID: "string",
  Session_ID: "string",
  Session_Key: "string",
  Client_Type: "string",
  Result_Code: 0,
  Result_Message: "string",
  Result_Data: {
    Full_Name: "string",
    Root_Zones: [
      {
        Zone_ID: 0,
        Zone_Name: "string",
      },
    ],
    Successor_Zones: [
      {
        Zone_ID: 0,
        Zone_Name: "string",
      },
    ],
    Water_Source_Groups: [
      {
        Group_ID: 0,
        Group_Name: "string",
        Zone_ID: 0,
      },
    ],
  },
  AccessDenied: "string",
};

// Using destructuring
const {
  Result_Data: {
    Root_Zones = [],
    Successor_Zones = [],
    Water_Source_Groups = [],
  } = {},
} = data;

// Using optional chaining operator (?.) and null coalescing operator (??)
const Root_ZonesAlt = data?.Result_Data?.Root_Zones ?? [];

console.log('Method1', Root_Zones);
console.log('Method2', Root_ZonesAlt);

有没有办法从示例JSON中提取适当的数据？

1 个答案: