Local storage in ionic 2 error

Question

I try to use this in my Ionic 2 application : https://ionicframework.com/docs/v2/storage/

I already run

cordova plugin add cordova-sqlite-storage --         


        

Answer 1

Since Ionic 2.2.0, it's recommended to use @ionic/storage version 2.0.0. Configuration in app.modules.ts has changed since the previous version. The error occurs if you haven't changed everything in the right way.

In app.modules.ts do following changes:

1. Remove Storage from providers

2. Change import statement:

   from: import { Storage } from '@ionic/storage';

   to: import { IonicStorageModule } from '@ionic/storage';

3. Add the following to the imports array:

   IonicStorageModule.forRoot()

The import array should look like below:

imports: [
  IonicModule.forRoot(MyApp),
  IonicStorageModule.forRoot()
],

NOTE: Do not make any change in imports of Storage in any other files.

Answer 2

Your app.module.ts should look like,

import { Storage } from '@ionic/storage';

export function provideStorage() {
  return new Storage(['sqlite', 'websql', 'indexeddb'], { name: 'database_name' });
}

@NgModule({
  declarations: [
  ],
  imports: [
    IonicModule.forRoot(MyApp)
  ],
  bootstrap: [IonicApp],
  entryComponents: [
  ],
  providers: [
    { provide: Storage, useFactory: provideStorage }, Storage
  ]
})

You have to use set() and get() methods to store and retrieve data in your pages. Have a look at Ionic 2 Storage Tutorial Blog with example video. Hope this helps