Slice from beginning if array ended javascript

Question

So I'm working on some filters where users can select even from ex: "Friday to Tuesday" but how to I slice these from an array of dates

var days = ["monday", "tuesday", "wednesday", "thursday", "friday", "saturday", "sunday"]

So how do I slice from index from 5 to 2 which should return:

["friday", "saturday", "sunday", "monday", "tuesday"]

What have you tried? Show your work so we can help you fix it. — Soviut
– Soviut, Commented Jul 22, 2019 at 1:13
This shows an example of treating the array in a circular manner: stackoverflow.com/a/17483207/11780044 — Horatius Cocles
– Horatius Cocles, Commented Jul 22, 2019 at 1:15
Possible duplicate of How to access array in circular manner in JavaScript — Horatius Cocles
– Horatius Cocles, Commented Jul 22, 2019 at 1:23

Mark · Accepted Answer · 2019-07-22 01:23:08Z

3

You could make a simple function that tests whether the end is smaller than the start and slice accordingly:

let days = ["monday", "tuesday", "wednesday", "thursday", "friday", "saturday", "sunday"]

const wrapslice = (arr, start, end)  =>{
    return end < start 
    ? arr.slice(start).concat(arr.slice(0, end))
    : arr.slice(start, end)
}
console.log(wrapslice(days, 5, 2))
console.log(wrapslice(days, 2, 5))
console.log(wrapslice(days, 4))

answered Jul 22, 2019 at 1:23

Mark

92.6k8 gold badges116 silver badges156 bronze badges

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

Comments

Gabriele Petrioli · Accepted Answer · 2019-07-22 01:14:43Z

2

You could use

var days = ["monday", "tuesday", "wednesday", "thursday", "friday", "saturday", "sunday"]

const selection = [...days.slice(4), ...days.slice(0, 2)];


console.log(selection);

answered Jul 22, 2019 at 1:14

Gabriele Petrioli

197k35 gold badges275 silver badges331 bronze badges

Comments

CertainPerformance · Accepted Answer · 2019-07-22 01:13:33Z

1

Friday is at index 4, so slice from index 4, and .concat with a slice of indicies 0 to 2:

const arr = ["monday", "tuesday", "wednesday", "thursday", "friday", "saturday", "sunday"]
console.log(arr.slice(4).concat(arr.slice(0, 2)));

answered Jul 22, 2019 at 1:13

CertainPerformance

373k55 gold badges354 silver badges359 bronze badges

Collectives™ on Stack Overflow

Slice from beginning if array ended javascript

3 Answers 3

Comments

Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related