<code><?<br />/**<br />* 转换为UNIX时间戳<br />*/<br />function gettime($d) {<br />　if(is_numeric($d))<br />　　return $d;<br />　else {<br />　　if(! is_string($d)) return 0;<br />　　if(ereg(":",$d)) {<br />　　　$buf = split(" +",$d);<br />　　　$year = split("[-/]",$buf[0]);<br />　　　$hour = split(":",$buf[1]);<br />　　　if(eregi("pm",$buf[2]))<br />　　　　$hour[0] += 12;<br />　　　return mktime($hour[0],$hour[1],$hour[2],$year[1],$year[2],$year[0]);<br />　　}else {<br />　　　$year = split("[-/]",$d);<br />　　　return mktime(0,0,0,$year[1],$year[2],$year[0]);<br />　　}<br />　}<br />}</code><code>/**<br />*<br />* DateAdd(interval,number,date)<br />* 返回已添加指定时间间隔的日期。<br />* Inetrval为表示要添加的时间间隔字符串表达式，例如分或天<br />* number为表示要添加的时间间隔的个数的数值表达式<br />* Date表示日期<br />*<br />* Interval(时间间隔字符串表达式)可以是以下任意值:<br />*　yyyy year年<br />*　q Quarter季度<br />*　m Month月<br />*　y Day of year一年的数<br />*　d Day天<br />*　w Weekday一周的天数<br />*　ww Week of year周<br />*　h Hour小时<br />*　n Minute分<br />*　s Second秒<br />*　w、y和d的作用是完全一样的，即在目前的日期上加一天，q加3个月，ww加7天。<br />*/<br />function DateAdd($interval, $number, $date) {<br />　$date = gettime($date);<br />　$date_time_array = getdate($date);<br />　$hours = $date_time_array["hours"];<br />　$minutes = $date_time_array["minutes"];<br />　$seconds = $date_time_array["seconds"];<br />　$month = $date_time_array["mon"];<br />　$day = $date_time_array["mday"];<br />　$year = $date_time_array["year"];<br />　switch ($interval) {<br />　　case "yyyy": $year +=$number; break;<br />　　case "q": $month +=($number*3); break;<br />　　case "m": $month +=$number; break;<br />　　case "y":<br />　　case "d":<br />　　case "w": $day+=$number; break;<br />　　case "ww": $day+=($number*7); break;<br />　　case "h": $hours+=$number; break;<br />　　case "n": $minutes+=$number; break;<br />　　case "s": $seconds+=$number; break;<br />　}<br />　$timestamp = mktime($hours ,$minutes, $seconds,$month ,$day, $year);<br />　return $timestamp;<br />}<br />/**<br />* DateDiff(interval,date1,date2)<br />* 返回两个日期之间的时间间隔<br />* intervals(时间间隔字符串表达式)可以是以下任意值:<br />*　 w　周<br />*　 d　天<br />*　 h　小时<br />*　 n　分钟<br />*　 s　秒<br />*/<br />function DateDiff ($interval, $date1,$date2) {<br />　// 得到两日期之间间隔的秒数<br />　$timedifference = gettime($date2) - gettime($date1);<br />　switch ($interval) {<br />　　case "w": $retval = bcdiv($timedifference ,604800); break;<br />　　case "d": $retval = bcdiv( $timedifference,86400); break;<br />　　case "h": $retval = bcdiv ($timedifference,3600); break;<br />　　case "n": $retval = bcdiv( $timedifference,60); break;<br />　　case "s": $retval = $timedifference; break;<br />　}<br />　return $retval;<br />}<br />?><br /><?<br />// 测试例<br />$d1 = "2002-01-11";<br />$d2 = date("Y-m-d",dateadd("d",15,$d1));<br />echo $d1."的". datediff("d",$d1,$d2)."天后是$d2<br>";<br />echo $d1."的10天前是".date("Y-m-d",dateadd("d",-10,$d1))."<br>";<br />$d3 = date("Y/m/d H:i:s");<br />echo "现在是".$d3."距离2002/2/12 12:59:59还有".datediff("s",$d3,"2002/2/12 12:59:59")."秒<br>";<br />?></code>