Storing/retrieving array from localstorage in Angular 2+

Question

I'm missing something elementary in my attempt to store and retrieve an array in localstorage in my Angular 4 app.

The app retrieves the array from the server into an 'any' typed variable called aToDo as:

{"qoption":"Trap Surveyor (<em>Competency for CM OAP<\/em>)"}

and stored in localstorage by:

localStorage.setItem('aToDo',JSON.stringify(this.aToDo));

It's retrieved from localstorage as:

this.aToDo = JSON.parse(localStorage.getItem('aToDo'));

A console.log of this.aToDo displays:

{"qoption":"Trap Surveyor (<em>Competency for CM OAP<\/em>)"}

But by this stage, things are stuffed as logging this.aToDo.qoption yields 'undefined' and the *ngFor used to list the array's contents generates the damning error:

Error: Cannot find a differ supporting object '{"qoption":"Trap Surveyor (<em>Competency for CM OAP<\/em>)"}' of type 'string'.

Where is my error? Thanks/Tom

Daniel H.J. · Accepted Answer · 2017-10-03 23:30:39Z

2

Two things:

console.log will output "undefined" by default alongside your output because it's not a return function. That's normal.
aToDo is an object, not an array. You cannot use ngFor on an object.

answered Oct 3, 2017 at 23:30

Daniel H.J.

4484 silver badges9 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

TomBaine Over a year ago

Thanks for getting me on track. Finally got to the point I wanted by interating objectKeys(aToDo). Cheers/T

Collectives™ on Stack Overflow

Storing/retrieving array from localstorage in Angular 2+

1 Answer 1

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related