Remove redundant if object javascript

Question

Hello I have an object that I want to browse and when a value is equal to true I fill an array. My code works but I don’t think it’s good to put so much if.

daysOfWeek: {
      lundi: true,
      mardi: true,
      mercredi: true,
      jeudi: false,
      vendredi: true,
      samedi: true,
      dimanche: true
    }

 let days = []

    if (daysOfWeek != null) {
        if (daysOfWeek.lundi === true) {
            days.push(2)
        }
        if (daysOfWeek.mardi === true) {
            days.push(3)
        }
        if (daysOfWeek.mercredi === true) {
            days.push(4)
        }
        if (daysOfWeek.jeudi === true) {
            days.push(5)
        }
        if (daysOfWeek.vendredi === true) {
            days.push(6)
        }
        if (daysOfWeek.samedi === true) {
            days.push(7)
        }
        if (daysOfWeek.dimanche === true) {
            days.push(1)
        }
    }
    return days 

days = [2,3,4,6,7,1]

I tried the switch/case but it doesn’t work for conditions.

Does anyone have another solution for me to explore?

Answer 1

I agree with this answer suggestion.

The number must be from 0 (Sunday) to 6 (Saturday).
In some locales, it may be 0 (Monday) to 6 (Sunday).

moment weekday

But if you want to set 1 as the first day of the week, I would suggest the code below

const daysOfWeek =  {
  lundi: true,
  mardi: true,
  mercredi: true,
  jeudi: false,
  vendredi: true,
  samedi: true,
  dimanche: true
}

const TOTAL_DAYS_OF_WEEK = 7;
const IS_SUNDAY_A_FIRST_DAY_OF_WEEK = true;
const FIRST_DAY_START_WITH = 1;

const result = [];
Object.values(daysOfWeek).forEach((value, index) => {
    if(value) {
        const dayOfWeek = (index + IS_SUNDAY_A_FIRST_DAY_OF_WEEK) % TOTAL_DAYS_OF_WEEK + FIRST_DAY_START_WITH;
        result.push(dayOfWeek);
    }
});

console.log(result)