Get Weeks In Month Through Javascript

Question

In Javascript, how do I get the number of weeks in a month? I can\'t seem to find code for this anywhere.

I need this to be able to know how many rows I need for a g

Answer 1

A little rudimentary, yet should cater for original post :

/**
 * @param {date} 2020-01-30
 * @return {int} count
 */
this.numberOfCalendarWeekLines = date => {

    // get total
    let lastDayOfMonth = new Date( new Date( date ).getFullYear(), new Date( date ).getMonth() + 1, 0 );

    let manyDaysInMonth = lastDayOfMonth.getDate();

    // itterate through month - from 1st
    // count calender week lines by occurance
    // of a Saturday ( s m t w t f s )
    let countCalendarWeekLines = 0;

    for ( let i = 1; i <= manyDaysInMonth; i++ ) {

        if ( new Date( new Date( date ).setDate( i ) ).getDay() === 6 ) countCalendarWeekLines++;

    }

    // days after last occurance of Saturday 
    // leaked onto new line?
    if ( lastDayOfMonth.getDay() < 6 ) countCalendarWeekLines++;

    return countCalendarWeekLines;

};