php - 2つの日付が少なくとも3か月異なるかどうかを確認するPHP

Question

PHPで、ある日付(文字列として指定)が別の日付と少なくとも3か月異なるかどうかを確認する方法(例が見つかりません):

$date1 = "2013-11-05";
$date2 = "2013-11-19";
//both dates is in form yyyy.mm.dd
differsThreeMonths($date1,$date2) { ???? return $differs; }
differsThreeMonths("2013-11-05","2014-05-02");//true 
differsThreeMonths("2014-01-01","2014-04-01");//true 
differsThreeMonths("2014-01-01","2014-03-31");//false
differsThreeMonths("2013-12-01","2014-01-15");//false
etc

ありがとうございました

Answer 1

$datetime1 = new DateTime('2013-07-01 12:00:00');
$datetime2 = new DateTime('2013-11-11 12:00:00');
$interval = $datetime1->diff($datetime2);
if(($interval->m>=3) || ($interval->y > 0))
echo "at least 3 months";
else
echo "Not greater than 3 months";

Answer 2

$datetime1 = new DateTime('2009-10-11');
$datetime2 = new DateTime('2009-10-13');
$interval = $datetime1->diff($datetime2);
var_dump($interaval);

http://www.php.net/manual/en/datetime.diff.php

Answer 3

試す：

function differsThreeMonths($date_str1, $date_str2) {
    if (strlen($date_str1) > 0 && strlen($date_str2) > 0) {
        $date1 = new DateTime($date_str1);
        $date2 = new DateTime($date_str2);
        $since_start = $date1->diff($date2);
        return (($since_start->y > 0) || ($since_start->m >= 3));
    } else {
        return -1; // ERROR CODE HERE
    }
}