Php 显示对象属性的更好迭代

我正在寻找一种更好的方法来迭代对象并显示其内容
表单控制器：

public function run(){ $tabteachers=''; if(!empty($_SESSION['apply']) && !empty($_SESSION['application'])){ $tabteachers = DB::getInstance()->select_teacher_id($_SESSION['login']); } require_once(VIEW_PATH.'formdeux.php'); } public function select_teacher_id($login){ $query = 'SELECT * FROM teachers,internships,students WHERE teachers.email_teacher = internships.email_responsible_internship AND students.registry_number_student = internships.registry_student_internship AND internships.registry_student_internship = '. $this->_db->quote ( $login ); $result = $this->_db->query ( $query ); if ($result->rowcount () != 0) { while ( $row = $result->fetch () ) { $teacher[]= new teacher ( $row->email_teacher,$row->firstname_teacher,$row->lastname_teacher,$row->responsible_internship_teacher,NULL); } return $teacher; } }

    <table>
        <thead>
            <tr>
                <th width="20%" class="decoration">contact</th>
            </tr>
        </thead>
            <tbody>
            <?php foreach ($tabteachers as $teacher) { ?>
                <tr>
                    <td>Lastname: <td>
                    <input type="text" name="lastnamepro" value="<?php echo $teacher->lastname_teacher() ?>" size="100px">
                </tr>
                <tr>
                    <td>Firstname: <td>
                    <input type="text" name="firstnamepro" value="<?php echo $teacher->firstname_teacher() ?>" size="100px">
                </tr>
                <tr>
                    <td>Email address: <td>
                    <input type="text" name="emailpro" value="<?php echo $teacher->email_teacher() ?>" size="100px">
                </tr>
                <tr>
                    <td>Service: <td>
                    <input type="text" name="servicepro" value="null" size="100px">
                </tr>
                <tr>
                    <td>mobile number: <td>
                    <input type="text" name="phonenumberpro" value="aucun numero" size="100px">
                </tr>
            <?php } ?>
            </tbody>
    </table><br>

private static $instance = null; private $_db; private function __construct() { try { $this->_db = new PDO ('mysql:host=localhost;dbname=ProjectWeb;charset=utf8', 'root', '' ); $this->_db->setAttribute ( PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION ); $this->_db->setAttribute ( PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_OBJ ); } catch ( PDOException $e ) { die ( 'Erreur de connexion à la base de donnée : ' . $e->getMessage () ); } } // Pattern Singleton public static function getInstance() { if (is_null ( self::$instance )) { self::$instance = new Db (); } return self::$instance; } 公共功能运行（）{ $tabteachers=''； 如果（！empty（$_会话['apply']）和&！empty（$_会话['application']））{ $tabteachers=DB:：getInstance（）->选择_teacher_id（$_SESSION['login']）； } 需要一次（查看路径'formdeux.php'）； } Db.class函数（）：

public function run(){ $tabteachers=''; if(!empty($_SESSION['apply']) && !empty($_SESSION['application'])){ $tabteachers = DB::getInstance()->select_teacher_id($_SESSION['login']); } require_once(VIEW_PATH.'formdeux.php'); } public function select_teacher_id($login){ $query = 'SELECT * FROM teachers,internships,students WHERE teachers.email_teacher = internships.email_responsible_internship AND students.registry_number_student = internships.registry_student_internship AND internships.registry_student_internship = '. $this->_db->quote ( $login ); $result = $this->_db->query ( $query ); if ($result->rowcount () != 0) { while ( $row = $result->fetch () ) { $teacher[]= new teacher ( $row->email_teacher,$row->firstname_teacher,$row->lastname_teacher,$row->responsible_internship_teacher,NULL); } return $teacher; } }

    <table>
        <thead>
            <tr>
                <th width="20%" class="decoration">contact</th>
            </tr>
        </thead>
            <tbody>
            <?php foreach ($tabteachers as $teacher) { ?>
                <tr>
                    <td>Lastname: <td>
                    <input type="text" name="lastnamepro" value="<?php echo $teacher->lastname_teacher() ?>" size="100px">
                </tr>
                <tr>
                    <td>Firstname: <td>
                    <input type="text" name="firstnamepro" value="<?php echo $teacher->firstname_teacher() ?>" size="100px">
                </tr>
                <tr>
                    <td>Email address: <td>
                    <input type="text" name="emailpro" value="<?php echo $teacher->email_teacher() ?>" size="100px">
                </tr>
                <tr>
                    <td>Service: <td>
                    <input type="text" name="servicepro" value="null" size="100px">
                </tr>
                <tr>
                    <td>mobile number: <td>
                    <input type="text" name="phonenumberpro" value="aucun numero" size="100px">
                </tr>
            <?php } ?>
            </tbody>
    </table><br>

private static $instance = null; private $_db; private function __construct() { try { $this->_db = new PDO ('mysql:host=localhost;dbname=ProjectWeb;charset=utf8', 'root', '' ); $this->_db->setAttribute ( PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION ); $this->_db->setAttribute ( PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_OBJ ); } catch ( PDOException $e ) { die ( 'Erreur de connexion à la base de donnée : ' . $e->getMessage () ); } } // Pattern Singleton public static function getInstance() { if (is_null ( self::$instance )) { self::$instance = new Db (); } return self::$instance; } 公共函数选择教师id（$login）{ $query='从教师、实习、学生中选择*，其中teachers.email\u teacher=internips.email\u responsible\u internival和student.registry\u number\u student=internips.registry\u student\u internival='。$this->\u db->quote（$login）； $result=$this->\u db->query（$query）； 如果（$result->rowcount（）！=0）{ 而（$row=$result->fetch（））{ $teacher[]=新教师（$row->email\u teacher，$row->firstname\u teacher，$row->lastname\u teacher，$row->responsible\u实习教师，空）； } 返回$teacher； } } 表单视图：

public function run(){ $tabteachers=''; if(!empty($_SESSION['apply']) && !empty($_SESSION['application'])){ $tabteachers = DB::getInstance()->select_teacher_id($_SESSION['login']); } require_once(VIEW_PATH.'formdeux.php'); } public function select_teacher_id($login){ $query = 'SELECT * FROM teachers,internships,students WHERE teachers.email_teacher = internships.email_responsible_internship AND students.registry_number_student = internships.registry_student_internship AND internships.registry_student_internship = '. $this->_db->quote ( $login ); $result = $this->_db->query ( $query ); if ($result->rowcount () != 0) { while ( $row = $result->fetch () ) { $teacher[]= new teacher ( $row->email_teacher,$row->firstname_teacher,$row->lastname_teacher,$row->responsible_internship_teacher,NULL); } return $teacher; } }

    <table>
        <thead>
            <tr>
                <th width="20%" class="decoration">contact</th>
            </tr>
        </thead>
            <tbody>
            <?php foreach ($tabteachers as $teacher) { ?>
                <tr>
                    <td>Lastname: <td>
                    <input type="text" name="lastnamepro" value="<?php echo $teacher->lastname_teacher() ?>" size="100px">
                </tr>
                <tr>
                    <td>Firstname: <td>
                    <input type="text" name="firstnamepro" value="<?php echo $teacher->firstname_teacher() ?>" size="100px">
                </tr>
                <tr>
                    <td>Email address: <td>
                    <input type="text" name="emailpro" value="<?php echo $teacher->email_teacher() ?>" size="100px">
                </tr>
                <tr>
                    <td>Service: <td>
                    <input type="text" name="servicepro" value="null" size="100px">
                </tr>
                <tr>
                    <td>mobile number: <td>
                    <input type="text" name="phonenumberpro" value="aucun numero" size="100px">
                </tr>
            <?php } ?>
            </tbody>
    </table><br>

private static $instance = null; private $_db; private function __construct() { try { $this->_db = new PDO ('mysql:host=localhost;dbname=ProjectWeb;charset=utf8', 'root', '' ); $this->_db->setAttribute ( PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION ); $this->_db->setAttribute ( PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_OBJ ); } catch ( PDOException $e ) { die ( 'Erreur de connexion à la base de donnée : ' . $e->getMessage () ); } } // Pattern Singleton public static function getInstance() { if (is_null ( self::$instance )) { self::$instance = new Db (); } return self::$instance; }

接触
姓氏：
我看到您已经将默认的fetch模式设置为fetch_OBJ，在这种特殊情况下，尽管我认为您可以使用PDO的fetchAll方法将整个结果集作为数组获取，然后对其进行迭代

 public function select_teacher_id($login){
   $query = 'SELECT * FROM teachers,internships,students WHERE
   teachers.email_teacher = internships.email_responsible_internship
  AND students.registry_number_student = internships.registry_student_internship
  AND internships.registry_student_internship = '. $this->_db->quote ( $login );


   $result = $this->_db->query ( $query );
       if ($result->rowcount () != 0) {
         //fetch the entire result set as a multi-dimensional assoc array
         $teachers_result = $result->fetchAll(PDO::FETCH_ASSOC); 
         return $teachers_result;
       }
 }

//看法

<table>
    <thead>
        <tr>
            <th width="20%" class="decoration">contact</th>
        </tr>
    </thead>
        <tbody>
        <?php foreach ($tabteachers as $teacher) { ?>
            <tr>
                <td>Lastname: <td>
                <input type="text" name="lastnamepro" value="<?php echo $teacher['lastname_teacher'] ?>" size="100px">
            </tr>
            <tr>
                <td>Firstname: <td>
                <input type="text" name="firstnamepro" value="<?php echo $teacher['firstname_teacher'] ?>" size="100px">
            </tr>
            <tr>
                <td>Email address: <td>
                <input type="text" name="emailpro" value="<?php echo $teacher['email_teacher'] ?>" size="100px">
            </tr>
            <tr>
                <td>Service: <td>
                <input type="text" name="servicepro" value="null" size="100px">
            </tr>
            <tr>
                <td>mobile number: <td>
                <input type="text" name="phonenumberpro" value="aucun numero" size="100px">
            </tr>
        <?php } ?>
        </tbody>
</table><br>


接触
姓氏：
有人能帮我吗？目前的设置有什么问题？您是否面临任何错误？或者你想优化它？@Vincent我收到一个错误，警告：为foreach（）提供的参数无效。它来自我实现的foreach。好的，你在Db类中使用PDO包装器吗？请查看下面的答案，如果你仍然看到foreach的参数无效错误，请在你的控制器中检查方法是否选择了\u teacher\u id（）返回任何数据，使用print_r（）或var_dump（）进行调试如果您是对的，则select_teacher_id（）函数在使用var_dump进行测试时返回null。我已经意识到，出于某种原因，$\u会话['login']没有按应有的方式保存登录id。另一方面，您显示元素的方式非常好。您可以这样做，或者如果您希望像前面一样将其作为对象，您可以传递PDO:：FETCH_OBJ标志，而不是FETCH_ASSOC，并在视图中相应地调用属性，即使这样也可以..完成一些测试后，我可以确认我的$_会话['login']为空，你说得对。但是我不明白为什么我给$\u SESSION[]的值不再存在了。我使用$u POST表保存了一个用户名。谢谢你的帮助，我真的很感激！