PHP 实现浏览记录并按日期分组

现有测试数据如下，要求实现如下图中的效果：

    array(4) {
     [0] => array(6) {
     ["visit_id"] => int(127)
     ["goods_id"] => int(16)
     ["visittime"] => int(1494399935)
     ["goods_name"] => string(53) "OPPO R9s 全网通4G+64G 双卡双待手机 玫瑰金"
     ["shop_price"] => string(6) "500.00"
     }
     [1] => array(6) {
     ["visit_id"] => int(124)
     ["goods_id"] => int(13)
     ["visittime"] => int(1494399921)
     ["goods_name"] => string(76) "SIEMENS/西门子 KA92NV09TI双开门家用对开门电冰箱变频旗舰款"
     ["shop_price"] => string(7) "4000.00"
     }
     [2] => array(6) {
     ["visit_id"] => int(123)
     ["goods_id"] => int(27)
     ["visittime"] => int(1494399903)
     ["goods_name"] => string(85) "爱他美白金版Aptamil 幼儿配方奶粉3段(12-36个月适用)900g(欧洲进口)"
     ["shop_price"] => string(6) "329.00"
     }
     [3] => array(6) {
     ["visit_id"] => int(120)
     ["goods_id"] => int(26)
     ["visittime"] => int(1494224263)
     ["goods_name"] => string(21) "欢乐谷免票一张"
     ["shop_price"] => string(5) "50.00"
     }
    }

还没实现之前我想这个代码不知道要O(n)呢还是更高的复杂度才能实现，细想一下，其实php的数组底层就是哈希实现的，如何简单利用这个特性使复杂度降到O(1)呢？

show me the code：

    /* 浏览记录按日期分组 */
    function groupVisit($visit)
    {
     $curyear = date('Y');
     $visit_list = [];
     foreach ($visit as $v) {
      if ($curyear == date('Y', $v['visittime'])) {
       $date = date('m月d日', $v['visittime']);
      } else {
       $date = date('Y年m月d日', $v['visittime']);
      }
      $visit_list[$date][] = $v;
     }
     return $visit_list;
    }

说明：入参 $visit 就是上面一开始的测试数据，函数中还对用户体验做了一些优化，比如，你的浏览记录中总是显示出今年的年份，是不是感觉有点冗余，所以如果是本年份的话，年份就要隐藏起来，其他年份还是照样显示出来。不然代码会更加简洁。

好了上面的测试数据经过该函数之后，再把返回值打印出来，有：

    array(2) {
     ["05月10日"] => array(3) {
     [0] => array(6) {
      ["visit_id"] => int(127)
      ["goods_id"] => int(16)
      ["visittime"] => int(1494399935)
      ["goods_name"] => string(53) "OPPO R9s 全网通4G+64G 双卡双待手机 玫瑰金"
      ["shop_price"] => string(6) "500.00"
     }
     [1] => array(6) {
      ["visit_id"] => int(124)
      ["goods_id"] => int(13)
      ["visittime"] => int(1494399921)
      ["goods_name"] => string(76) "SIEMENS/西门子 KA92NV09TI双开门家用对开门电冰箱变频旗舰款"
      ["shop_price"] => string(7) "4000.00"
     }
     [2] => array(6) {
      ["visit_id"] => int(123)
      ["goods_id"] => int(27)
      ["visittime"] => int(1494399903)
      ["goods_name"] => string(85) "爱他美白金版Aptamil 幼儿配方奶粉3段(12-36个月适用)900g(欧洲进口)"
      ["shop_price"] => string(6) "329.00"
     }
     }
     ["05月08日"] => array(1) {
     [0] => array(6) {
      ["visit_id"] => int(120)
      ["goods_id"] => int(26)
      ["visittime"] => int(1494224263)
      ["goods_name"] => string(21) "欢乐谷免票一张"
      ["shop_price"] => string(5) "50.00"
     }
     }
    }

对的，这正是我想要的效果。

以上所述是小编给大家介绍的PHP 实现浏览记录并按日期分组，希望对大家有所帮助，如果大家有任何疑问请给我留言，小编会及时回复大家的。在此也非常感谢大家对脚本之家网站的支持！