PHP输出时间差函数代码

<?php  
date_default_timezone_set('PRC'); //默认时区  
echo "今天:",date("Y-m-d",time()),"<br>";  
echo "今天:",date("Y-m-d",strtotime("18 june 2008")),"<br>";  
echo "昨天:",date("Y-m-d",strtotime("-1 day")), "<br>";  
echo "明天:",date("Y-m-d",strtotime("+1 day")), "<br>";  
echo "一周后:",date("Y-m-d",strtotime("+1 week")), "<br>";  
echo "一周零两天四小时两秒后:",date("Y-m-d G:H:s",strtotime("+1 week 2 days 4 hours 2 seconds")), "<br>";  
echo "下个星期四:",date("Y-m-d",strtotime("next Thursday")), "<br>";  
echo "上个周一:".date("Y-m-d",strtotime("last Monday"))."<br>";  
echo "一个月前:".date("Y-m-d",strtotime("last month"))."<br>";  
echo "一个月后:".date("Y-m-d",strtotime("+1 month"))."<br>";  
echo "十年后:".date("Y-m-d",strtotime("+10 year"))."<br>";  
?>

//获取当天的星期（1-7）
function GetWeek($times)
{
    $res = date('w', strtotime($times));
    if($res==0)
       $res=7;
    return $res;
}
//获取当天时间
function GetTime($times)
{
    $res = date('H:i', strtotime($times));
    return $res;
}
//获取现在过几月的的时间
function GetMonth($Month,$type='l')
{
    if(!strcmp($type,'b'))
      $res=date("Y-m-d H:i:s",strtotime("-$Month months"));
    if(!strcmp($type,'l'))
      $res=date("Y-m-d H:i:s",strtotime("+$Month months"));
    return $res;
}
//获取当前时间
function GetCurrentDateTime()
{
    $res=date("Y-m-d H:i:s",time());
    return $res;
}
//获取当前时间隔几小时之前或之后的时间
function GetDiffHours($hours,$type='l')
{
  if(!strcmp($type,'b'))
     $res=date("Y-m-d H:i:s",strtotime("-$hours hour"));
  if(!strcmp($type,'l'))
     $res=date("Y-m-d H:i:s",strtotime("+$hours hour"));
  return $res;     
}
//间隔几分钟之前或之后的时间
function GetDiffMinute($Minute,$type='l')
{
  if(!strcmp($type,'b'))
     $res=date("Y-m-d H:i:s",strtotime("-$Minute minute"));
  if(!strcmp($type,'l'))
     $res=date("Y-m-d H:i:s",strtotime("+$Minute minute"));
  return $res;     
}
//间隔几秒之前或之后的时间
function GetDiffSec($sec,$type='l')
{
  if(!strcmp($type,'b'))
     $res=date("Y-m-d H:i:s",strtotime("-$sec second"));
  if(!strcmp($type,'l'))
     $res=date("Y-m-d H:i:s",strtotime("+$sec second"));
  return $res;     
}

//间隔几个星期之前或之后的时间
function GetDiffWeek($Week,$type='l')
{
  if(!strcmp($type,'b'))
     $res=date("Y-m-d H:i:s",strtotime("-$Week week"));
  if(!strcmp($type,'l'))
     $res=date("Y-m-d H:i:s",strtotime("+$Week week"));
  return $res;     
}
// 间隔几天之间的时间
function GetDiffDays($days,$type='l')
{
  if(!strcmp($type,'b'))
     $res=date("Y-m-d H:i:s",strtotime("-$days day"));
  if(!strcmp($type,'l'))
     $res=date("Y-m-d H:i:s",strtotime("+$days day"));
  return $res;     
}
//间隔几年之前或之后的时间
function GetDiffYears($year,$type='l')
{
  if(!strcmp($type,'b'))
     $res=date("Y-m-d H:i:s",strtotime("-$year year"));
  if(!strcmp($type,'l'))
     $res=date("Y-m-d H:i:s",strtotime("+$year year"));
  return $res;     
}