使用PHP将时间戳四舍五入到最近的时间
例如，如果要创建“四舍五入”的时间戳，请精确到15分钟，以此为参考：
function roundTime($amount, $units = 'm', $time = null)
{
if (is_null($time)) {
$time = time();
}
if ($amount == 0) {
$amount = 1;
}
switch ($units){
case 'm':
$roundBy = 60 * $amount;
break;
case 'h':
$time = $time + 60 * 60 * $amount;
$roundBy = 60 * 60 * $amount;
break;
case 'd':
$time = $time + 60 * 60 * 24 * $amount;
$roundBy = 60 * 60 * 24 * $amount;
break;
}
return round($time / $roundBy) * $roundBy;
}
echo "\n";
echo date('r', roundTime(15, 'm'));
echo "\n";
echo date('r', roundTime(2, 'h'));
echo "\n";
echo date('r', roundTime(3, 'd'));
echo "\n";
echo date('r', roundTime(-3, 'd'));
echo "\n";