如何在领域数据库javascript中保存数据

Question

我是React-native的新手，在我的应用程序中使用领域数据库。 我想通过json预先填充数据。 我尝试使用componentDidMount（）函数，并使用for循环插入数据。 任何指导都会有所帮助。

以下是我的代码：

//模式文件：

import booksdata from './books.json';

const Realm = require('realm');

const BooksSchema = {
    name: 'Books',
    primaryKey: 'id',
    properties: {
        id: 'int', // primary key
        name: 'string',
        author: 'string',
        publisher: 'string',
    },
};

const databaseSchema = {
    path: 'books.realm',
    schema: [BooksSchema],
    schemaVersion: 0, // optional
};

export const mountData = () => new Promise((resolve, reject) => {
    Realm.open(databaseSchema)
        .then((realm) => {
            // Create Realm objects and write to local storage
            realm.write(() => {
                booksdata.forEach(obj => realm.create(databaseSchema, {
                    id: Math.floor(Date.now() / 1000),
                    name: obj.name,
                    author: obj.author,
                    publisher: obj.publisher,
                }));
            });
        });
});

//在我的索引文件中，名为componentDidMount：

 componentDidMount() {
    mountData().then().catch((error) => {
      alert(`Insert error ${error}`);
    });
  }

//我收到以下警告

Possible Unhandled Promise Rejection (id: 0):
Error: objectType must be of type 'string', got ([object Object])
Error: objectType must be of type 'string', got ([object Object])
    at sendRequest (blob:http://localhost:8081/d198fbe8-8b32-4037-93a7-df5a46af4f15:62352:45)
    at sendRequest (blob:http://localhost:8081/d198fbe8-8b32-4037-93a7-df5a46af4f15:62385:24)
    at Object.callMethod (blob:http://localhost:8081/d198fbe8-8b32-4037-93a7-df5a46af4f15:62128:22)
    at Realm.<anonymous> (blob:http://localhost:8081/d198fbe8-8b32-4037-93a7-df5a46af4f15:61983:28)
    at blob:http://localhost:8081/d198fbe8-8b32-4037-93a7-df5a46af4f15:61408:15
    at tryCallOne (blob:http://localhost:8081/d198fbe8-8b32-4037-93a7-df5a46af4f15:16056:14)
    at blob:http://localhost:8081/d198fbe8-8b32-4037-93a7-df5a46af4f15:16157:17
    at blob:http://localhost:8081/d198fbe8-8b32-4037-93a7-df5a46af4f15:2884:21
    at _callTimer (blob:http://localhost:8081/d198fbe8-8b32-4037-93a7-df5a46af4f15:2773:9)
    at _callImmediatesPass (blob:http://localhost:8081/d198fbe8-8b32-4037-93a7-df5a46af4f15:2809:9)

Answer 1

您可以将JSON数据解析为JavaScript对象，但是这些对象必须匹配您的架构。

let objs = JSON.parse(data);
realm.write(() => {
    objs.forEach((obj) => realm.create('data', obj));
}

其中'data'是模式的名称。

Answer 2

感谢大伙们！ 我犯了一个非常愚蠢的错误。 在架构文件中，当我在领域中插入记录时，我没有传递架构的名称。 而不是databaseSchema，我应该传递模式的名称，即BooksSchema.name（Books）

export const mountData = () => new Promise((resolve, reject) => {
    Realm.open(databaseSchema)
        .then((realm) => {
            // Create Realm objects and write to local storage
            realm.write(() => {
                booksdata.forEach(obj => realm.create(BooksSchema.name, {
                    id: Math.floor(Date.now() / 1000),
                    name: obj.name,
                    author: obj.author,
                    publisher: obj.publisher,
                }));
            });
        });
});