php中的时间处理

  <?

  /**

  * 转换为UNIX时间戳

  */

  function gettime($d) {

  if(is_numeric($d))

  return $d;

  else {

  if(! is_string($d)) return 0;

  if(ereg(":",$d)) {

  $buf = split(" +",$d);

  $year = split("[-/]",$buf[0]);

  $hour = split(":",$buf[1]);

  if(eregi("pm",$buf[2]))

  $hour[0] += 12;

  return mktime($hour[0],$hour[1],$hour[2],$year[1],$year[2],$year[0]);

  }else {

  $year = split("[-/]",$d);

  return mktime(0,0,0,$year[1],$year[2],$year[0]);

  }

  }

  }

  /**

  *

  * DateAdd(interval,number,date)

  * 返回已添加指定时间间隔的日期。

  * Inetrval为表示要添加的时间间隔字符串表达式,例如分或天

  * number为表示要添加的时间间隔的个数的数值表达式

  * Date表示日期

  *

  * Interval(时间间隔字符串表达式)可以是以下任意值:

  *  yyyy year年

  *  q Quarter季度

  *  m Month月

  *  y Day of year一年的数

  *  d Day天

  *  w Weekday一周的天数

  *  ww Week of year周

  *  h Hour小时

  *  n Minute分

  *  s Second秒

  *  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。

  */

  function DateAdd($interval, $number, $date) {

  $date = gettime($date);

  $date_time_array = getdate($date);

  $hours = $date_time_array["hours"];

  $minutes = $date_time_array["minutes"];

  $seconds = $date_time_array["seconds"];

  $month = $date_time_array["mon"];

  $day = $date_time_array["mday"];

  $year = $date_time_array["year"];

  switch ($interval) {

  case "yyyy": $year +=$number; break;

  case "q": $month +=($number*3); break;

  case "m": $month +=$number; break;

  case "y":

  case "d":

  case "w": $day+=$number; break;

  case "ww": $day+=($number*7); break;

  case "h": $hours+=$number; break;

  case "n": $minutes+=$number; break;

  case "s": $seconds+=$number; break;

  }

  $timestamp = mktime($hours ,$minutes, $seconds,$month ,$day, $year);

  return $timestamp;

  }

  /**

  * DateDiff(interval,date1,date2)

  * 返回两个日期之间的时间间隔

  * intervals(时间间隔字符串表达式)可以是以下任意值:

  *   w  周

  *   d  天

  *   h  小时

  *   n  分钟

  *   s  秒

  */

  function DateDiff ($interval, $date1,$date2) {

  // 得到两日期之间间隔的秒数

  $timedifference = gettime($date2) - gettime($date1);

  switch ($interval) {

  case "w": $retval = bcdiv($timedifference ,604800); break;

  case "d": $retval = bcdiv( $timedifference,86400); break;

  case "h": $retval = bcdiv ($timedifference,3600); break;

  case "n": $retval = bcdiv( $timedifference,60); break;

  case "s": $retval = $timedifference; break;

  }

  return $retval;

  }

  ?>

  <?

  // 测试例

  $d1 = "2002-01-11";

  $d2 = date("Y-m-d",dateadd("d",15,$d1));

  echo $d1."的". datediff("d",$d1,$d2)."天后是$d2<br>";

  echo $d1."的10天前是".date("Y-m-d",dateadd("d",-10,$d1))."<br>";

  $d3 = date("Y/m/d H:i:s");

  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>";

  ?>