get_month_range.php

<?php

function get_month_range($start_date, $end_date) 
{
    if (!is_int($start_timestamp)) :
        $start_timestamp = strtotime($start_date);
        if ($start_timestamp === false) :
            throw new Exception("Invalid value provided for the start date!");
        endif;
    endif; 
    
    if (!is_int($end_timestamp)) :
        $end_timestamp = strtotime($end_date);
        if ($end_timestamp === false) :
            throw new Exception("Invalid value provided for the end date!");
        endif;
    endif;
    
    if ($start_timestamp > $end_timestamp) :
        throw new Exception("The start time cannot be greater than the end time!");
    endif;
    
    $start_month = (int)date('n', $start_timestamp);
    $start_year = (int)date('Y', $start_timestamp);
    $start_month_timestamp = mktime(null, null, null, $start_month, 1, $start_year);
    
    $end_month = (int)date('n', $end_timestamp);
    $end_year = (int)date('Y', $end_timestamp);
    $end_month_timestamp = mktime(null, null, null, $end_month, 1, $end_year);
    
    $months = array();
    $current_month_timestamp = $start_month_timestamp;
    while ($current_month_timestamp <= $end_month_timestamp) :
        
        // This is the value that gets added to the returned array.
        // It can be whatever you want -- string value, another array, etc.
        // At this point in the function execution, $current_month_timestamp 
        // is a timestamp for the first day of the current month in the loop,
        // and that's what you'll want to use to generate the return value.
        $months[] = date('F Y', $current_month_timestamp);
        
        $current_month = (int)date('n', $current_month_timestamp);
        $current_year = (int)date('Y', $current_month_timestamp);
        if ($current_month++ > 12) :
            $current_month = 1;
            $current_year++;
        endif;
        $current_month_timestamp = mktime(null, null, null, $current_month, 1, $current_year);
    endwhile;
    
    return $months;
}

$start_date = 'October 30, 1986';
$end_date = 'June 1, 1987';
$months = get_month_range($start_date, $end_date);
var_dump($months);