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Retrieving multiple key values ​​from Ionic2 storage

Using Ionic2 repository, I did the following in a custom provider, I can confirm that the key-value pairs are set and I can get them individually:

this.storage.set('one', 1);
this.storage.set('two', 2);
this.storage.set('three', 3);

The problem is that I have a function in one of my pages that needs to access all three of these values ​​for an HTTP request, so I can get one of them like this:

this.storage.get('one').then((value) => {
    // Preform http request sending value in POST data
});

But how do I get multiple key values ​​at once? Do I need to embed these calls or is there an easier way to access multiple keys in one call so that I can do something like:

this.storage.get(['one', 'two', 'three']).then((values) => {
    console.log(values.one); // I dunno, something like this
});
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2 answers


You can simply do it like below.

this.storage.forEach( (value, key, index) => {
    console.log("value", value);//store these values as you wish
    console.log("key", key);
    console.log("Index" index);
})


From Api Doc.

 /**
   * Iterate through each key,value pair.
   * @param iteratorCallback a callback of the form (value, key, iterationNumber)
   * @return Promise that resolves when the iteration has finished.
   */

  forEach(iteratorCallback: (value: any, key: string, iterationNumber: Number) => any): Promise<null> {
    return this._dbPromise.then(db => db.iterate(iteratorCallback));
  }
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I have used Promise.all for this purpose



Promise.all([this.storage.get("email"), this.storage.get("username")]).then(values => {

      console.log("email", values[0]);
      console.log("username", values[1]);

      // every other thing can happen here e.g call a method

});
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