http://php.net/manual/en/ref.datetime.phpから
関数を呼び出すときに $precision を 1 に変更し、日付の前後に任意のテキストを追加します。日付オブジェクトをタイムスタンプに変換する必要がありますが、それは問題にはなりません。
/**
* this code assumes php >= 5.1.0. if using < 5.1, read
* php.net/strtotime and change the condition for checking
* for failure from strtotime()
*/
// $t1, $t2: unix times, or strtotime parseable
// $precision: max number of units to output
// $abbr: if true, use "hr" instead of "hour", etc.
function date_diff ($t1, $t2, $precision = 6, $abbr = false) {
if (preg_match('/\D/', $t1) && ($t1 = strtotime($t1)) === false)
return false;
if (preg_match('/\D/', $t2) && ($t2 = strtotime($t2)) === false)
return false;
if ($t1 > $t2)
list($t1, $t2) = array($t2, $t1);
$diffs = array(
'year' => 0, 'month' => 0, 'day' => 0,
'hour' => 0, 'minute' => 0, 'second' => 0,
);
$abbrs = array(
'year' => 'yr', 'month' => 'mth', 'day' => 'day',
'hour' => 'hr', 'minute' => 'min', 'second' => 'sec'
);
foreach (array_keys($diffs) as $interval) {
while ($t2 >= ($t3 = strtotime("+1 ${interval}", $t1))) {
$t1 = $t3;
++$diffs[$interval];
}
}
$stack = array();
foreach ($diffs as $interval => $num)
$stack[] = array($num, ($abbr ? $abbrs[$interval] : $interval) . ($num != 1 ? 's' : ''));
$ret = array();
while (count($ret) < $precision && ($item = array_shift($stack)) !== null) {
if ($item[0] > 0)
$ret[] = "{$item[0]} {$item[1]}";
}
return implode(', ', $ret);
}
$t1 = 'Feb 4, 2008 12:16:00';
$t2 = 'Jul 3, 2006 16:15:30';
echo date_diff($t1, $t2), "\n",
date_diff($t1, $t2, 3), "\n",
date_diff($t1, $t2, 2, true), "\n";
?>