Get week number in month from date in PHP?

Question

I have an array of random dates (not coming from MySQL). I need to group them by the week as Week1, Week2, and so on upto Week5.

What I have is this:

Answer 1

$date = new DateTime('first Monday of this month');
$thisMonth = $date->format('m');
$mondays_arr = [];

// Get all the Mondays in the current month and store in array
while ($date->format('m') === $thisMonth) {
    //echo $date->format('Y-m-d'), "\n";
    $mondays_arr[] = $date->format('d');
    $date->modify('next Monday');
}

// Get the day of the week (1-7 from monday to sunday)
$day_of_week = date('N') - 1;

// Get the day of month (1 to 31) 
$current_week_monday_date = date('j') - $day_of_week;

/*$day_of_week = date('N',mktime(0, 0, 0, 2, 11, 2020)) - 1;
$current_week_monday_date = date('j',mktime(0, 0, 0, 2, 11, 2020)) - $day_of_week;*/

$week_no = array_search($current_week_monday_date,$mondays_arr) + 1;
echo "Week No: ". $week_no;