What is the proper way to implement ref in typescript?

Currently, I am in the process of learning how to use Vue3 + Typescript. Previously, I have developed Vue2 applications using plain JavaScript. In my current project, I am attempting to define a reactive variable within the setup() function:

setup() {
    // defining a single note
    interface Note {
      id: string
      creationDate: string
      text: string
      tags: string[]
      deleted: boolean
    }
    // holding all notes in the app
    let allNotes: ref(Note[])  // ← this implementation is incorrect
    let allnotes: Note[]  // ← this syntax is correct but non-reactive
    
    (...)
  }

I am seeking assistance with the proper syntax for creating a reactive Array of Note. Can someone provide guidance on this matter?

Answer №1

It needs to go in between the symbols <>:

let allItems= ref<Item[]>([]) 

When using the ref keyword, it automatically detects the type based on the initial value, as shown here:

const age=ref(0) //age is of type number

Ref definition :

interface Ref<T> {
  value: T
}

function ref<T>(value: T): Ref<T>

Answer №2

There is no necessity to create a reactive object specifically for that purpose. It is intended for an object.

As suggested by @Boussadjra Brahim, you can include a type in the ref function like so:

let reactiveNoteArray = ref<Note[]>([]); //Remember to add the angle brackets when using custom types and interfaces

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