如何显示索引数组的特殊词？

Question

I still newbie and faced with one challenge.

I want to display specific word in < div > when user wants to find out the datetime for example:

let today = new Date;

let time = today.getHours()
let hours= [
    'work',
    'work',
    'work',
    'work',
    'work',
    'work',
    'work',
    'fun',
    'work',
    'work',
    'work',
    'work',
    'work',
    'work',
    'work',
    'fun',
    'fun',
    'fun',
    'work',
    'work',
    'fun',
    'fun',
    'fun',
    'fun',
  ]
let hoursName = hours[today.getHours()];
console.log(hoursName);

My code works, but it a little bit not properly I think. If length of my array, in future, will 999 indexes? To fill each index, I'll spend many time, is it possible somehow add ( if, else if ) into array?

Answer 1

You can create an array which contains the start and end index for "fun" values. Like for the 24 example in the question, It can be created as below:

var funRanges = [[7, 7], [15, 17], [21, 23]]; // [[Start, end]] (Both inclusive)

Then using a function, you can check if your hour value lies in any of the ranges. Like below:

 var funRanges = [[7, 7], [15, 17], [21, 23]]; // [[Start, end]] (Both inclusive) var getHourName = (hour) => funRanges.some(x => hour >= x[0] && hour <= x[1])? 'fun': 'work'; console.log(getHourName(1)) // work

In future, You can just add new ranges into your rangeArray, and the code will still work fine.

Answer 2

You can maintain array of arrays and each sub array is window of "last index" and "type of item".

In the following same
0-6 --> work
7-7 --> fun
8-23 --> movie

 const get = (index) => { // array of array, each array is "last index" and "type" const hours = [ [6, "work"], [7, "fun"], [23, "movie"], ]; const slot = hours.find((arr) => arr[0] >= index); return slot[1]; }; console.log(get(5)); console.log(get(7)); console.log(get(15));