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Storage

The Storage API provides a key-value store for simple data.

Mobile OS’s may periodically clear data set in window.localStorage, so this API should be used instead of window.localStorage. This API will fall back to using localStorage when running as a Progressive Web App.

On iOS this plugin will use UserDefaults and on Android SharedPreferences. Stored data is cleared if the app is uninstalled.

Note: this API is not meant for high-performance data storage applications. Take a look at using SQLite or a separate data engine if your application will store a lot of items, have high read/write load, or require complex querying.

Working with JSON

Storage works on Strings only. However, storing JSON blobs is easy: just JSON.stringify the object before calling set, then JSON.parse the value returned from get. See the example below for more details.

This method can also be used to store non-string values, such as numbers and booleans.

Example

import { Plugins } from '@capacitor/core';

const { Storage } = Plugins;


// JSON "set" example
async setObject() {
  await Storage.set({
    key: 'user',
    value: JSON.stringify({
      id: 1,
      name: 'Max'
    })
  });
}

// JSON "get" example
async getObject() {
  const ret = await Storage.get({ key: 'user' });
  const user = JSON.parse(ret.value);
}

async setItem() {
  await Storage.set({
    key: 'name',
    value: 'Max'
  });
}

async getItem() {
  const { value } = await Storage.get({ key: 'name' });
  console.log('Got item: ', value);
}

async removeItem() {
  await Storage.remove({ key: 'name' });
}

async keys() {
  const { keys } = await Storage.keys();
  console.log('Got keys: ', keys);
}

async clear() {
  await Storage.clear();
}

API

get(…)

get(options: { key: string; }) => Promise<{ value: string | null; }>

Get the value with the given key.

Param Type
options { key: string; }

Returns: Promise<{ value: string; }>


set(…)

set(options: { key: string; value: string; }) => Promise<void>

Set the value for the given key

Param Type
options { key: string; value: string; }

remove(…)

remove(options: { key: string; }) => Promise<void>

Remove the value for this key (if any)

Param Type
options { key: string; }

clear()

clear() => Promise<void>

Clear stored keys and values.


keys()

keys() => Promise<{ keys: string[]; }>

Return the list of known keys

Returns: Promise<{ keys: string[]; }>


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