如何在Angular 5中使用IndexedDB？

Question

在Angular 5/React中是否存在使用indexedDB的材料？我正在寻找可以帮助我实现数据救援或更好的东西,一个在浏览器中的数据库,虽然它不是本地商店,因为5 MB的限制

Answer 1

使用 ngx-indexed-db npm 库：

npm install ngx-indexed-db

导入 NgxIndexedDBModule 并启动它：

import { NgxIndexedDBModule } from 'ngx-indexed-db';

const dbConfig: DBConfig  = {
  name: 'MyDb',
  version: 1,
  objectStoresMeta: [{
    store: 'people',
    storeConfig: { keyPath: 'id', autoIncrement: true },
    storeSchema: [
      { name: 'name', keypath: 'name', options: { unique: false } },
      { name: 'email', keypath: 'email', options: { unique: false } }
    ]
  }]
};

@NgModule({
  ...
  imports: [
    ...
    NgxIndexedDBModule.forRoot(dbConfig)
  ],
  ...
})

迁移：

import { NgxIndexedDBModule, DBConfig } from 'ngx-indexed-db';

// Ahead of time compiles requires an exported function for factories
export function migrationFactory() {
  // The animal table was added with version 2 but none of the existing tables or data needed
  // to be modified so a migrator for that version is not included.
  return {
    1: (db, transaction) => {
      const store = transaction.objectStore('people');
      store.createIndex('country', 'country', { unique: false });
    },
    3: (db, transaction) => {
      const store = transaction.objectStore('people');
      store.createIndex('age', 'age', { unique: false });
    }
  };
}

const dbConfig: DBConfig  = {
  name: 'MyDb',
  version: 3,
  objectStoresMeta: [{
    store: 'people',
    storeConfig: { keyPath: 'id', autoIncrement: true },
    storeSchema: [
      { name: 'name', keypath: 'name', options: { unique: false } },
      { name: 'email', keypath: 'email', options: { unique: false } }
    ]
  }, {
    // animals added in version 2
    store: 'animals',
    storeConfig: { keyPath: 'id', autoIncrement: true },
    storeSchema: [
      { name: 'name', keypath: 'name', options: { unique: true } },
    ]
  }],
  // provide the migration factory to the DBConfig
  migrationFactory
};

@NgModule({
  ...
  imports: [
    ...
    NgxIndexedDBModule.forRoot(dbConfig)
  ],
  ...
})

NgxIndexedDB 服务首先导入服务：

import { NgxIndexedDBService } from 'ngx-indexed-db';

...
  export class AppComponent {
    constructor(private dbService: NgxIndexedDBService){
    }
  }

Answer 2

我使用Dexie，因为它是一个更成熟、更轻量级的库，并且具有所有功能。兼容 VueJs、React、Angular 和 Vanilla JS

替代ngx-indexed-db