Question

我正在使用以下逻辑对从SQL数据库中读取的数据进行排序 -

<a href='string_functions.php?sort=desc'>Sort By Type</a>
<?php  
    if( isset( $_GET['sort'] ) and $_GET['sort'] == 'desc')  {
        $query = "SELECT * FROM `function list` ORDER BY `function type` DESC";
    } else {
        #Read from Database
        $query = "SELECT * FROM `function list`";
    }
    $data_buffer = $conn -> query($query);
?>

然后我使用 $data_buffer 来显示表格 function list

中的元组

我想做 -

<a href='string_functions.php?sort=desc'>Sort By Type</a>

切换 ASC 和 DESC 操作。是否可以这样做？

我知道我可以使用两个链接，如 -

<a href='string_functions.php?sort=asc'>Sort By Type</a>
<a href='string_functions.php?sort=desc'>Sort By Type</a>

每个用于不同的操作，但是只使用一个链接是否可以这样做？

Answer 1

我没有测试过此代码，但它会对您有所帮助并且我使用了会话，因为它会帮助您进行分页，但它不是强制性的，您也可以根据需要使用简单变量

<?php
  if( isset( $_GET['sort'] ) and $_GET['sort'] == 'desc')
  {
   $_SESSION['sort_type']='DESC'; //you can set using normal variable also instead of SESSION
   $_SESSION['sort_arrow']='v';
   $_SESSION['sort_link']='asc';
  }
  else
  {
    $_SESSION['sort_type']='ASC';
    $_SESSION['sort_arrow']='^';
    $_SESSION['sort_link']='desc';
  }

  $query = "SELECT * FROM `function list` ORDER BY `function type` '".$_SESSION['sort_type']."'";
  ?>
  <a href="string_functions.php?sort=<?php echo $_SESSION['sort_link'];?>">
   <?php echo $_SESSION['sort_arrow'];?>
</a>

Answer 2

在CSS的帮助下，我能够做到的代码很少

<强> PHP：

<?php  
    if(isset( $_GET['sort'] ) and $_GET['sort'] == 'desc')
        $hide = 'hide';
    else
        $hide = '';
?>
<a href='string_functions.php?sort=desc' class="<?php echo $hide;?>">Sort By Type(DESC)</a>
<?php  
    if( isset( $_GET['sort'] ) and $_GET['sort'] == 'desc' )  {
        $query = "SELECT * FROM `function list` ORDER BY `function type` DESC";
        ?>
        <a href='string_functions.php?sort=asc'>Sort By Type(ASC)</a>
    <?php 
    } else if(isset( $_GET['sort'] ) and $_GET['sort'] == 'asc' ) { ?>
    <?php
        #Read from Database
        $query = "SELECT * FROM `function list` ORDER BY `function type` ASC";
    } else {
        $query = "SELECT * FROM `function list`";
    }
    $data_buffer = $conn -> query($query);
?>

<强> CSS：

<style>
    .hide {
        display: none;
    }
</style>

Answer 3

试试这个：

<a href='string_functions.php?sort=desc'>Sort By Type</a>

替换为：

if(isset( $_GET['sort'] ) and $_GET['sort'] == 'desc') 
    echo "<a href='string_functions.php?sort=asc'>ASC</a>";
else
    echo "<a href='string_functions.php?sort=desc'>DESC</a>";

升序和降序排序操作的一个查询字符串

3 个答案: