把HH:MM:SS格式的时间字符串转换成秒数，可以使用date_parse函数解析具体的时间信息。

PHP

$time = '21:30:10';

$parsed = date_parse($time);

$seconds = $parsed['hour'] * 3600 + $parsed['minute'] * 60 + $parsed['second'];

echo $seconds;

?>

下面PHP函数是讲时间转换成多少天/多少小时/多少分

function get_stay_time($timestamp,$is_hour = 1,$is_minutes = 1)

{

$CI =& get_instance();

if(empty($timestamp) || $timestamp <= 60) {

return false;

}

$time = time();

$remain_time = $time - $timestamp;

$day = floor($remain_time / (3600*24));

$day = $day > 0 ? $day.'天' : '';

$hour = floor(($remain_time % (3600*24)) / 3600);

$hour = $hour > 0 ? $hour.'小时' : '';

if($is_hour && $is_minutes) {

$minutes = floor((($remain_time % (3600*24)) % 3600) / 60);

$minutes = $minutes > 0 ? $minutes.'分' : '';

return $day.$hour.$minutes;

}

if($hour) {

return $day.$hour;

}

return $day;

}