php - $_GET 变量在分页代码中未定义

Question

我不熟悉 PHP，并且在如何在分页代码中创建 $_GET 或 $_SESSION 变量方面遇到了 2 周的问题。情况是:

我从 index.php 页面获得一个值，当我单击它(例如照片/图像)时，我使用 GET 获取该值，然后当我将该值回显到我的 Category 时.php 页面，该值使用“echo”在我的 BODY 页面中投影正常，但我想要的是当页面加载时，GET 变量将是我的分页代码中的搜索键。但是，当我在分页代码中回显 GET 变量时，我得到的结果是“UNDEFINED”，这意味着该变量未在我的分页代码中定义。这是我的分页。哦，是的，我对我的代码进行了更改，我很抱歉，但这是我使用 $mycat 和 GET 方法的先前代码。对不起。

<?php
session_start();
$mycat =$_GET['category'];
//PHP code for specific search
$action = (isset($_REQUEST['action'])&& $_REQUEST['action'] !=NULL)?$_REQUEST['action']:'';

if($action == 'ajax'){

    /* Connect To Database*/
    $dbname = 'ufile';
    $link = mysql_connect("localhost","root","") or die("Couldn't make connection.");
    $db = mysql_select_db($dbname, $link) or die("Couldn't select database");

    $mycat =  htmlspecialchars ($_GET['category']) ? trim($_GET['category']) : ''; //SQL injection protection

    include 'pagination.php'; //include pagination file

    //pagination variables
    $page = (isset($_REQUEST['page']) && !empty($_REQUEST['page']))?$_REQUEST['page']:1;
    $per_page = 10; //how many records you want to show
    $adjacents  = 4; //gap between pages after number of adjacents
    $offset = ($page - 1) * $per_page;

    echo 'Result: ' .$mycat; //////////THIS IS THE GET VALUE....WHICH TURNS OUT AS UNDEFINED IN VALUE IT SHOULD BE 'PHOTOS/IMAGES, AUDIOS/VIDEOS or COMPRESSED FILES'....PLEASE HELP ME.

    //Count the total number of row in your table*/
    $count_query   = mysql_query("SELECT COUNT(category) AS numrows FROM udocs WHERE category LIKE '%" . $mycat . "%'"); //Count the number of search result here (tagal kitang hinanap dito ka lng pala)
    $row     = mysql_fetch_array($count_query);
    $numrows = $row['numrows'];
    $total_pages = ceil($numrows/$per_page);
    $reload = 'cat_index.php';

    //main query to fetch the data
    $result = mysql_query("SELECT * FROM udocs WHERE category LIKE '%" . $mycat . "%' ORDER BY date_upload LIMIT $offset,$per_page");


    //loop through fetched data
    while($test = mysql_fetch_array($result)){

        $id = $test['file_name'];   
            $fileid=$test['file_path'];

            echo "<div class='content'>";
                echo'<div class="img_content"  ><img src='.$test['file_icon'].' style=height:50px;width:50px;float:left;margin-right:10px;></div>';
                echo"<font  color='black'; font size='2px !important' ;font family='Century Gothic, sans-serif' ;letter spacing='2px';>Name:   </font><font color='yellowgreen'; font size='2px !important' ;font family='Century Gothic, sans-serif' ;letter spacing='2px';>" .$test['file_name']."</font><br>";
                    echo"<font color='black'; font size='2px !important' ;font family='Century Gothic, sans-serif' ;letter spacing='2px';>Category:   </font><font color='gray'; font size='2px !important' ;font family='Century Gothic, sans-serif' ;letter spacing='2px';>" .$test['category']."</font></font><font color='skyblue'; font size='2px !important' ;font family='Century Gothic, sans-serif' ;letter spacing='2px';>   |   </font><font color='black'; font size='2px !important' ;font family='Century Gothic, sans-serif' ;letter spacing='2px';>Size:   </font><font color='gray'; font size='2px !important' ;font family='Century Gothic, sans-serif' ;letter spacing='2px';>" .$test['file_size']."</font></font><font color='skyblue'; font size='2px !important' ;font family='Century Gothic, sans-serif' ;letter spacing='2px';>   |   </font><font color='black'; font size='2px !important' ;font family='Century Gothic, sans-serif' ;letter spacing='2px';>Credits to:   </font><font color='gray'; font size='2px !important' ;font family='Century Gothic, sans-serif' ;letter spacing='2px';>" .$test['author']."</font><font color='skyblue'; font size='2px !important' ;font family='Century Gothic, sans-serif' ;letter spacing='2px';>   |   </font><font color='black'; font size='2px !important' ;font family='Century Gothic, sans-serif' ;letter spacing='2px';>Date Uploaded:   </font><font color='gray'; font size='2px !important' ;font family='Century Gothic, sans-serif' ;letter spacing='2px';>" .$test['date_upload']."</font><br>";
                    echo"<font color='black'; font size='2px !important' ;>Description:". $test['description']. "</font><br>";
                    echo"<a href ='download.php?file_path=$fileid' ><font color='orange' title='$mycat'>Download File</p></a>";
            echo        "</div>";

}
    //BOTTOM
    if ($numrows==0)
    {

    }
    else
    {
        echo paginate($reload, $page, $total_pages, $adjacents);
    }

    //header('Location:index.php');
    //die();

} // end of ajax first condition
else
{

?>
<body>

<?php
 echo 'You are searching for: '.$mycat;
?>

</body>

<?php } ?>

Answer 1

如果 $_REQUEST 允许您访问参数，但 $_GET 不允许，请尝试 $_POST，这意味着使用的 HTTP 方法是 POST 而不是 GET。还要检查提交到此脚本的表单/javascript。 $_REQUEST 是一个包罗万象的超全局变量，包含 get 和 post 参数(还有 cookies!)。

$_REQUEST

我还建议深入阅读一下 HTTP 协议(protocol)，它可以帮助解决此类问题:)

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