Declare array index in typescript

Question

I have this AjaxResponse Interface :

interface AjaxResponse {
    calendar: {
        dates: {
            date: string,
            hours: {
                hour: string,
                id: number,
                status: string,
                client: {
                    name: string,
                    surname: string,
                    email: string,
                    phone: string,
                    id: number
                }
            }[]
        }[]
    },
    rights: string,
    listenerUrl: string
}

I will iterate through a list of dates and edit some of them :

let dates: AjaxResponse['calendar']['dates']
let i: number
let l: number

    receive(response: AjaxResponse) {
                dates = response.calendar.dates
                l = dates.length
                for (i; i < l; i++) {
                    calendar.editDates(dates[i])
                }

The edit dates function is as follow :

editDates(newDate: AjaxResponse['calendar']['dates']) {
    }

The dates[i] won't compile because my last function is expecting an array. How could I declare a single date rather than list of dates in my last function ?

Edit : Found a working solution by creating two interfaces :

interface AjaxResponse {
    calendar: {
        dates: AjaxResponseDate[]
    },
    rights: string,
    listenerUrl: string
}

interface AjaxResponseDate {
    date: string,
    hours: {
        hour: string,
        id: number,
        status: string,
        client: {
            name: string,
            surname: string,
            email: string,
            phone: string,
            id: number
        }
    }
}

Titian Cernicova-Dragomir · Accepted Answer · 2018-09-07 05:27:16Z

3

To get the type of an item in an array, you can use a type query by number:

function editDates(newDate: AjaxResponse['calendar']['dates'][number]) {
}

The solution to have t interfaces is also a possible one, but you can keep a single type if you want.

answered Sep 7, 2018 at 5:27

Titian Cernicova-Dragomir

253k37 gold badges465 silver badges395 bronze badges

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

1 Comment

Ado Ren Over a year ago

Yes both can be use, but your answer fits my interrogation perfectly. Thanks

Collectives™ on Stack Overflow

Declare array index in typescript

1 Answer 1

1 Comment

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

1 Comment

Related