PHP获取特定日期最近发生的年份

Question

I am working on a script that will determine when a specific calendar date most recently occurred.

This post, Get the year of a specified month in previous 12 months?, is the basis of my current beta. It was written for a monthly result and not a specific date.

<?php
if (empty($_GET['m'])) {
    $m = "October";
} else {
    $m = htmlspecialchars($_GET['m']);
}

if (empty($_GET['d'])) {
    $d = "1";
} else {
    $d = htmlspecialchars($_GET['d']);
}

date_default_timezone_set('America/Los_Angeles');

$m = date('m', strtotime($m));

$c = (mktime(0,0,0,$m,$d) < time())
    ? mktime(0,0,0,$m,$d)
    : mktime(0,0,0,$m,$d,date("Y") -1);

$from = date('F jS', $c) . " last occurred in " . date('Y', $c) . ".";

echo $from;
?>

The result of the default value, October 1 is: "October 1st last occurred in 2012."

For June 11th, as a random example: "June 11th last occurred in 2013."

All date results are TRUE, except for the result for February 29th: "March 1st last occurred in 2013." Obviously, this is a false statement since the desired result is: "February 29th last occurred in 2012."

I'm kind of stuck, what is the best way to add a true leap year result?

Answer 1

This is calculating last true year. Replace with following codes.

<?php
if (empty($_GET['m'])) {
    $m = "October";
    } else {
    $m = htmlspecialchars($_GET['m']);
}

if (empty($_GET['d'])) {
    $d = "1";
    } else {
    $d = htmlspecialchars($_GET['d']);
}

date_default_timezone_set('America/Los_Angeles');

$y = date('Y');
if($m == "February" && $d == "29") $y = $y - ($y % 4);
$m = date('m', strtotime($m));

$c = (mktime(0,0,0,$m,$d) < time()) ? mktime(0,0,0,$m,$d,$y) : mktime(0,0,0,$m,$d,$y);

$from = date('F jS', $c) . " last occurred in " . $y . ".";

echo $from;
?>

Results

For 2013: Result 2012
For 2012: Result 2012
For 2011: Result 2008
For 2010: Result 2008