必须收藏的php实用代码片段

30. 计算两个日期的差

/**

• Calculate differences between two dates with precise semantics. Based on PHPs DateTime::diff()
• implementation by Derick Rethans. Ported to PHP by Emil H,2011-05-02. No rights reserved.
• See here for original code:
• http://svn.php.net/viewvc/php/php-src/trunk/ext/date/lib/tm2unixtime.c?revision=302890&view=markup
• http://svn.php.net/viewvc/php/php-src/trunk/ext/date/lib/interval.c?revision=298973&view=markup
  /
  function _date_range_limit($start,$end,$adj,$a,$b,$result)
  {
  if ($result[$a] < $start) {
  $result[$b] -= intval(($start - $result[$a] - 1) / $adj) + 1;
  $result[$a] += $adj intval(($start - $result[$a] - 1) / $adj + 1);
  }
  if ($result[$a] >= $end) {
  $result[$b] += intval($result[$a] / $adj);
  $result[$a] -= $adj * intval($result[$a] / $adj);
  }
  return $result;
  }
  function _date_range_limit_days($base,$result)
  {
  $days_in_month_leap = array(31,31,29,30,31);
  $days_in_month = array(31,28,31);
  _date_range_limit(1,13,12,"m","y",&$base);
  $year = $base["y"];
  $month = $base["m"];
  if (!$result["invert"]) {
  while ($result["d"] < 0) {
  $month--;
  if ($month < 1) {
  $month += 12;
  $year--;
  }
  $leapyear = $year % 400 == 0 || ($year % 100 != 0 && $year % 4 == 0);
  $days = $leapyear ? $days_in_month_leap[$month] : $days_in_month[$month];
  $result["d"] += $days;
  $result["m"]--;
  }
  } else {
  while ($result["d"] < 0) {
  $leapyear = $year % 400 == 0 || ($year % 100 != 0 && $year % 4 == 0);
  $days = $leapyear ? $days_in_month_leap[$month] : $days_in_month[$month];
  $result["d"] += $days;
  $result["m"]--;
  $month++;
  if ($month > 12) {
  $month -= 12;
  $year++;
  }
  }
  }
  return $result;
  }
  function _date_normalize($base,$result)
  {
  $result = _date_range_limit(0,60,"s","i",$result);
  $result = _date_range_limit(0,"h",24,"d",$result);
  $result = _date_range_limit_days(&$base,&$result);
  $result = _date_range_limit(0,$result);
  return $result;
  }
  /**
• Accepts two unix timestamps.
  */
  function _date_diff($one,$two)
  {
  $invert = false;
  if ($one > $two) {
  list($one,$two) = array($two,$one);
  $invert = true;
  }
  $key = array("y","s");
  $a = array_combine($key,array_map("intval",explode(" ",date("Y m d H i s",$one))));
  $b = array_combine($key,$two))));
  $result = array();
  $result["y"] = $b["y"] - $a["y"];
  $result["m"] = $b["m"] - $a["m"];
  $result["d"] = $b["d"] - $a["d"];
  $result["h"] = $b["h"] - $a["h"];
  $result["i"] = $b["i"] - $a["i"];
  $result["s"] = $b["s"] - $a["s"];
  $result["invert"] = $invert ? 1 : 0;
  $result["days"] = intval(abs(($one - $two)/86400));
  if ($invert) {
  _date_normalize(&$a,&$result);
  } else {
  _date_normalize(&$b,&$result);
  }
  return $result;
  }
  $date = "2014-12-04 19:37:22";
  echo '

  ';
  
  print_r( _date_diff( strtotime($date),time() ) );
  
  echo '

  ';
  ?>

  31. 删除文件夹内容

  语法：

  32. 搜索和高亮字符串中的关键字

  ",$text ); } return $text; }

  语法：

  33. 写入文件

  34. 根据 URL 下载图片

  语法：

  35. 检测 URL 是否有效

语法：