Question

我正在尝试使用foreach函数但是收到错误。这是我的代码：

function student_image_list(){
    global $host, $dbname, $user, $pass;
    $DBH = new PDO("mysql:host=$host;dbname=$dbname", $user, $pass);
    $STH = $DBH->query("SELECT DISTINCT folder_name from school_students_images");
    $STH->setFetchMode(PDO::FETCH_ASSOC);
    $row = $STH->fetch();
    return $row;
}

我想打印表school_students_images中的所有唯一文件夹名称，我正在尝试这样做：

$folder_name1 = student_image_list();
foreach($folder_name1['folder_name'] as $folder_name)  
    { 
        echo ' <div class="mws-panel grid_2">
               <div class="mws-panel-header">
               <span>'.$folder_name.'</span>
               </div>                            
               </div>';
    }

错误警告：第41行的student_image_list_raw.php中为foreach（）提供的参数无效这一行的错误

foreach($folder_name1['folder_name'] as $folder_name)

请帮忙。

Answer 1

您只获取一行，而且似乎没有＆＃39; folder_name＆＃39;关键，你必须

function student_image_list(){
    global $host, $dbname, $user, $pass;
    $DBH = new PDO("mysql:host=$host;dbname=$dbname", $user, $pass);
    $STH = $DBH->query("SELECT DISTINCT folder_name from school_students_images");
    $STH->setFetchMode(PDO::FETCH_ASSOC);
    return $STH;
}

$STH = student_image_list();
while (($row = $STH->fetch()) !== false) {
    echo ' <div class="mws-panel grid_2">
           <div class="mws-panel-header">
           <span>'.$row['folder_name'].'</span>
           </div>                            
           </div>';

}

Foreach和DISTINCT具有函数PHP mysql

1 个答案: