将时间差转换为字符串提示

通过传入数据库中存储的文章发表时的UNIX时间戳，来转化为例如 几分钟前，几小时前，几天前 这样的提示。如微博

 这看起来更加人性化，好吧，上代码

 1 <?php
 2  class timeAgo
 3  {  
 4     static $timeagoObject;   
 5     private $rustle;
 6     private $unit;
 7     
 8      private function __construct()
 9      {
10          
11      }                
12      private function __clone(){ }
13      public static function getObject()
14      {
15          if(! (self::$timeagoObject instanceof self) )
16                 self::$timeagoObject = new timeAgo();
17               
18          return self::$timeagoObject;  
19      }
20      private function count_int($unix_C)   // main function
21      {
22          if(! (isset($unix_C) || is_numeric($unix_C)) )
23              return 'don\'t find parameter';
24              
25          $d = time()-$unix_C ;   // $d - unix time difference value 
26          $d_int =(int)floor($d/60) ; // minimum unit -- minutes   unix/60
27          
28          $this->unit = 0 ;   // is minutes,hour or day?
29          
30          if($d_int < 60){   // minutes   in one hour  3600
31             $this->rustle = $d_int;
32             $this->unit = 1;  
33             }
34            else if($d_int < 720){  //hour    in one day  3600*12
35                  $this->rustle = floor($d_int/60);
36                  $this->unit = 2 ;
37                  }   
38               else if($d_int < 7200){  //day  in ten days  3600*12*10
39                       $this->rustle = floor($d_int/720);
40                       $this->unit = 3 ;
41                       }
42                   else{
43                       $this->rustle = $d ;
44                       $this->unit = 4 ;   
45                       } 
46      }
47      public function piece_str($C)
48      {
49           $this->count_int($C);
50              
51           $u = ''; 
52           switch( $this->unit )
53           {
54              case 1:
55                   $u = 'minute';
56                   break;
57              case 2:
58                   $u = 'hour';
59                   break;
60              case 3:
61                   $u = 'day';
62                   break;
63              case 4:
64                   $u = '';
65                   break;
66              case 0:
67                   return 'sorry , get time is fail';     
68           }
69           if($this->unit < 4)
70           {
71           if($this->rustle > 1)
72                return (string)$this->rustle.$u.'s ago';
73           else if($this->rustle == 1)
74                  return (string)$this->rustle.$u.'ago';
75               else
76                   return 'Just now';  
77           }
78      }
79      /*  example:   $ago = timeAgo::getObject();
80       *             echo $ago->piece_str($unix);    
81       *             // 2 days ago
82      */
83  }
84 ?>