如何使用来自indexedDB的承诺在@ngrx/ initialState中设置核心

import { createInitialStateProvider } from '@ngrx/initial-state';

@NgModule({
  providers: [
    createInitialStateProvider({
      getInitialState: () => {
        // 在这里获取indexedDB中的数据并返回作为初始状态
        return new Promise((resolve, reject) => {
          // 使用indexedDB API获取数据
          const request = indexedDB.open('yourDatabaseName');
          request.onsuccess = (event) => {
            const db = event.target.result;
            const transaction = db.transaction('yourStoreName', 'readonly');
            const objectStore = transaction.objectStore('yourStoreName');
            const getRequest = objectStore.get('yourKey');
            getRequest.onsuccess = (event) => {
              const data = event.target.result;
              resolve(data);
            };
            getRequest.onerror = (event) => {
              reject(event.target.error);
            };
          };
          request.onerror = (event) => {
            reject(event.target.error);
          };
        });
      }
    })
  ]
})
export class AppModule { }

import { Component, OnInit } from '@angular/core';
import { initialState } from '@ngrx/initial-state';

@Component({
  selector: 'app-root',
  template: `
    <div>
      <!-- 在这里使用初始状态 -->
    </div>
  `
})
export class AppComponent implements OnInit {
  constructor(private initialState: initialState) { }

  ngOnInit() {
    this.initialState.subscribe((state) => {
      // 在这里使用初始状态
    });
  }
}