php将日期格式转换成xx天前的格式

本文实例讲述了php将日期格式转换成xx天前格式的方法。分享给大家供大家参考。具体如下：

这段代码可以把时间格式化成3天前，5秒前，2年前的形式

    // convert a date into a string that tells how long ago
    // that date was.... eg: 2 days ago, 3 minutes ago.
    function ago($d) {
     $c = getdate();
     $p = array('year', 'mon', 'mday', 'hours', 'minutes', 'seconds');
     $display = array('year', 'month', 'day', 'hour', 'minute', 'second');
     $factor = array(0, 12, 30, 24, 60, 60);
     $d = datetoarr($d);
     for ($w = 0; $w < 6; $w++) {
     if ($w > 0) {
      $c[$p[$w]] += $c[$p[$w-1]] * $factor[$w];
      $d[$p[$w]] += $d[$p[$w-1]] * $factor[$w];
     }
     if ($c[$p[$w]] - $d[$p[$w]] > 1) { 
      return ($c[$p[$w]] - $d[$p[$w]]).' '.$display[$w].'s ago';
     }
     }
     return '';
    }
    // you can replace this if need be. 
    // This converts my dates returned from a mysql date string 
    // into an array object similar to that returned by getdate().
    function datetoarr($d) {
     preg_match("/([0-9]{4})(\\-)([0-9]{2})(\\-)([0-9]{2})([0-9]{2})(\\:)([0-9]{2})(\\:)([0-9]{2})/",$d,$matches);
     return array( 
     'seconds' => $matches[10], 
     'minutes' => $matches[8], 
     'hours' => $matches[6], 
     'mday' => $matches[5], 
     'mon' => $matches[3], 
     'year' => $matches[1], 
     );
    }

希望本文所述对大家的php程序设计有所帮助。