开发中经常用到时间的一些操作，比如昨天，今天，前天，近七天，一周等等。
class time{ ???private $year;//年 ???private $month;//月 ???private $day;//天 ???private $hour;//小时 ???private $minute;//分钟 ???private $second;//秒 ???private $microtime;//毫秒 ???private $weekday;//星期 ???private $longDate;//完整的时间格式 ???private $diffTime;//两个时间的差值 ???//返回年份 time：时间格式为时间 2018-8-21 ???function getyear($time="",$type=""){ ???????if($time==""){ ???????????$time=time(); ???????} ???????if($type==1){ ???????????return $this->year=date("y",$time); //返回两位的年份 18 ???????}else{ ???????????return $this->year=date("Y",$time); //返回四位的年份 2018 ???????} ???} ???//返回当前时间的月份 time：时间格式为时间 2018-8-21 ???function getmonth($time="",$type=""){ ???????if($time==""){ ???????????$time=time(); ???????} ???????switch($type){ ???????????case 1:$this->month=date("n",$time);//返回格式 8 ???????????break; ???????????case 2:$this->month=date("m",$time);//返回格式 08 ???????????break; ???????????case 3:$this->month=date("M",$time);//返回格式 Aug ???????????break; ???????????case 4:$this->month=date("F",$time);//返回格式 August ???????????break; ???????????default:$this->month=date("n",$time); ???????} ???????return $this->month; ????} ???//返回当前时间的天数 time：时间格式为时间 2018-8-21 ????function getday($time="",$type=""){ ???????if($time==""){ ???????????$time=time(); ???????} ???????if($type==1){ ???????????$this->day=date("d",$time);//返回格式 21 ???????}else{ ???????????$this->day=date("j",$time);//返回格式 21 ???????} ???????return $this->day; ???} ???//返回当前时间的小时 ?2018-08-21 1:19:21 20:19:21 ????function gethour($time="",$type=""){ ???????if($time==""){ ???????????$time=time(); ???????} ????????switch($type){ ???????????case 1:$this->hour=date("H",$time);//格式： 1 20 ???????????break; ???????????case 2:$this->hour=date("h",$time);//格式 ?01 08 ???????????break; ???????????case 3:$this->hour=date("G",$time);//格式 ?1 20 ???????????break; ???????????case 4:$this->hour=date("g",$time);//格式 ?1 8 ???????????break; ????????????default :$this->hour=date("H",$time); ???????} ???????return $this->hour; ???} ???//返回当前时间的分钟数 1:9:18 ?????function getminute($time="",$type=""){ ???????if($time==""){ ???????????$time=time(); ???????} ???????$this->minute=date("i",$time); //格式 ?09 ???????return $this->minute; ???} ???//返回当前时间的秒数 ?20:19:01 ???function getsecond($time="",$type=""){ ???????if($time==""){ ???????????$time=time(); ???????} ???????$this->second=date("s",$time); //格式 ?01 ???????return $this->second; ???} ???//返回当前时间的星期数 ????function getweekday($time="",$type=""){ ???????if($time==""){ ???????????$time=time(); ????????} ???????if($type==1){ ???????????$this->weekday=date("D",$time);//格式 ?Sun ???????}else if($type==2){ ???????????$this->weekday=date("l",$time); //格式 Sunday ???????}else{ ???????????$this->weekday=date("w",$time);//格式 数字表示 0--6 ???????} ???????return $this->weekday; ???} ???//比较两个时间的大小 格式 2018-8-21 8:4:3 ?????function compare($time1,$time2){ ???????$time1=strtotime($time1); ???????$time2=strtotime($time2); ???????if($time1>=$time2){ ?//第一个时间大于等于第二个时间 返回1 否则返回0 ???????????return 1; ???????}else{ ???????????return -1; ???????} ???} ???//比较两个时间的差值 ???function diffdate($time1="",$time2=""){ ???????//echo $time1.‘------‘.$time2.‘<br>‘; ???????if($time1==""){ ???????????$time1=date("Y-m-d H:i:s"); ????????} ???????if($time2==""){ ????????????$time2=date("Y-m-d H:i:s"); ????????} ???????$date1=strtotime($time1); ???????$date2=strtotime($time2); ???????if($date1>$date2){ ???????????$diff=$date1-$date2; ????????}else{ ???????????$diff=$date2-$date1; ???????} ???????if($diff>=0){ ???????????$day=floor($diff/86400); ???????????$hour=floor(($diff%86400)/3600); ???????????$minute=floor(($diff%3600)/60); ???????????$second=floor(($diff%60)); ???????????$this->diffTime=‘相差‘.$day.‘天‘.$hour.‘小时‘.$minute.‘分钟‘.$second.‘秒‘; ????????} ???????return $this->diffTime; ???} ???//返回 X年X月X日 ???function buildDate($time="",$type=""){ ???????if($type==1){ ??????????????$this->longDate = $this->getyear($time) . ‘年‘ . $this->getmonth($time) . ‘月‘ . $this->getday($time) . ‘日‘; ?????????}else{ ???????????$this->longDate = $this->getyear($time) . ‘年‘ . $this->getmonth($time) . ‘月‘ . $this->getday($time) . ‘日‘.$this->gethour($time).‘:‘.$this->getminute($time).‘:‘.$this->getsecond($time); ?????????} ???????return $this->longDate; ?????}}
实例化这个对象
??$time_var = "2018-08-21"; ??$obj = new time(); ??$year = $obj->getyear($time_var); ??echo($year);PHP封装时间类
原文地址：https://www.cnblogs.com/qixidi/p/10202518.html