扩展php中的时间函数DateDiff和DateAdd

function DateDiff($part, $begin, $end) { $diff = strtotime($end) - strtotime($begin); switch($part) { case "y": $retval = bcdiv($diff, (60 * 60 * 24 * 365)); break; case "m": $retval = bcdiv($diff, (60 * 60 * 24 * 30)); break; case "w": $retval = bcdiv($diff, (60 * 60 * 24 * 7)); break; case "d": $retval = bcdiv($diff, (60 * 60 * 24)); break; case "h": $retval = bcdiv($diff, (60 * 60)); break; case "n": $retval = bcdiv($diff, 60); break; case "s": $retval = $diff; break; } return $retval; } function DateAdd($part, $number, $date) { $date_array = getdate(strtotime($date)); $hor = $date_array["hours"]; $min = $date_array["minutes"]; $sec = $date_array["seconds"]; $mon = $date_array["mon"]; $day = $date_array["mday"]; $yar = $date_array["year"]; switch($part) { case "y": $yar += $number; break; case "q": $mon += ($number * 3); break; case "m": $mon += $number; break; case "w": $day += ($number * 7); break; case "d": $day += $number; break; case "h": $hor += $number; break; case "n": $min += $number; break; case "s": $sec += $number; break; } return date("Y-m-d H:i:s", mktime($hor, $min, $sec, $mon, $day, $yar)); } Function DateAdd($part, $n, $date) { switch($part) { case "y": $val = date("Y-m-d H:i:s", strtotime($date ." +$n year")); break; case "m": $val = date("Y-m-d H:i:s", strtotime($date ." +$n month")); break; case "w": $val = date("Y-m-d H:i:s", strtotime($date ." +$n week")); break; case "d": $val = date("Y-m-d H:i:s", strtotime($date ." +$n day")); break; case "h": $val = date("Y-m-d H:i:s", strtotime($date ." +$n hour")); break; case "n": $val = date("Y-m-d H:i:s", strtotime($date ." +$n minute")); break; case "s": $val = date("Y-m-d H:i:s", strtotime($date ." +$n second")); break; } return $val; }