考试下拉菜单没有出现

时间：2012-10-06 15:42:46

标签： php html database mysqli

我正在尝试检索考试（会话），具体取决于教师从上一个下拉菜单中选择的模块。

例如：

从下拉列表中选择的模块： CHI2332（ModuleId）高级数据库系统（ModuleName）

考试（会话）显示在下拉列表中：

AAA（SessionId）24-04-2012（SessionDate）11:00:00（会话时间）
ARF（SessionId）13-06-2012（SessionDate）14:00:00（会话时间）
EFT（SessionId）10-09-2012（SessionDate）09:00:00（会议时间）

它应该在下拉菜单中显示上面的考试，因为这些考试与从模块下拉菜单中选择的moduleId相匹配，而这些考试的TeacherId属于登录到此页面的教师用户名。

问题是，在考试下拉菜单中，即使模块对于这些考试是合法的，也似乎无法找到任何考试，因此它应该在下拉菜单中显示这些考试。

它只是输出以下错误：

Sessions: Notice: Undefined variable: sessionHTML in /.../ on line 178

如何让考试出现在下拉菜单中？

以下是数据库表：

会话表： 

SessionId SessionDate SessionTime ModuleId  
AAA       24-04-2012  11:00:00    CHI2332 
ARF       13-06-2012  14:00:00    CHI2332 
EFT       10-09-2012  09:00:00    CHI2332

模块表： 

ModuleId  ModuleName
CHI2332   Advanced Database Systems

下面是php / mysqli代码：

<?php

         // connect to the database
 include('connect.php');

  /* check connection */
  if (mysqli_connect_errno()) {
    printf("Connect failed: %s\n", mysqli_connect_error());
    die();
  }

   $courseid = (isset($_POST['courseid'])) ? $_POST['courseid'] : '';

   ?>

       <h1>DELETING AN ASSESSMENT</h1>

        <form action="<?php echo htmlentities($_SERVER['PHP_SELF']); ?>" method="post">
         <p>Course ID: <input type="text" name="courseid" /><input id="courseSubmit" type="submit" value="Submit" name="submit" /></p>      
        </form>


        <?php
if (isset($_POST['submit'])) {

        $query = "
                 SELECT cm.CourseId, cm.ModuleId, 
                 c.CourseName,
                 m.ModuleName
                 FROM Course c
                 INNER JOIN Course_Module cm ON c.CourseId = cm.CourseId
                 JOIN Module m ON cm.ModuleId = m.ModuleId
                 WHERE
                 (c.CourseId = ?)
                 ORDER BY c.CourseName, m.ModuleId
                ";

    $qrystmt=$mysqli->prepare($query);
    // You only need to call bind_param once
    $qrystmt->bind_param("s",$courseid);
    // get result and assign variables (prefix with db)

    $qrystmt->execute(); 

    $qrystmt->bind_result($dbCourseId,$dbModuleId,$dbCourseName,$dbModuleName);

     $qrystmt->store_result();

    $num = $qrystmt->num_rows();

    if($num ==0){
        echo "<p>Sorry, No Course was found with this Course ID '$courseid'</p>";
    } else { 

        $dataArray = array();

 while ( $qrystmt->fetch() ) { 
          // data array
          $dataArray[$dbCourseId]['CourseName'] = $dbCourseName; 
          $dataArray[$dbCourseId]['Modules'][$dbModuleId]['ModuleName'] = $dbModuleName; 
           // session data
          $_SESSION['idcourse'] = $dbCourseId;
          $_SESSION['namecourse'] = $dbCourseName;

    }

     foreach ($dataArray as $courseId => $courseData) {

          $output = ""; 

          $output .= "<p><strong>Course:</strong> " . $courseId .  " - "  . $courseData['CourseName'] . "</p>";

       $moduleHTML = ""; 
       $moduleHTML .= '<select name="module" id="modulesDrop">'.PHP_EOL;
       $moduleHTML .= '<option value="">Please Select</option>'.PHP_EOL;      
            foreach ($courseData['Modules'] as $moduleId => $moduleData) {        

            $moduleHTML .= "<option value='$moduleId'>" . $moduleId . " - " . $moduleData['ModuleName'] ."</option>".PHP_EOL;        
  } 
            }
            $moduleHTML .= '</select>';

      echo $output;

        }


        ?>

         <form action="<?php echo htmlentities($_SERVER['PHP_SELF']); ?>" method="post">
         <p>Module: <?php echo $moduleHTML; ?><input id="moduleSubmit" type="submit" value="Submit" name="modulesubmit" /></p>      
        </form> 



        <?php

    }

 if (isset($_POST['modulesubmit'])) {

     var_dump($_POST['modulesDrop']);

            $sessionquery = "
                 SELECT SessionId, SessionDate, SessionTime, ModuleId
                 FROM Session
                 WHERE
                 (ModuleId = ?)
                 ORDER BY SessionDate, SessionTime 
                ";

    $sessionqrystmt=$mysqli->prepare($sessionquery);
    // You only need to call bind_param once
    $sessionqrystmt->bind_param("s",$_POST['modulesDrop']);
    // get result and assign variables (prefix with db)

    $sessionqrystmt->execute(); 

    $sessionqrystmt->bind_result($dbSessionId,$dbSessionDate,$dbSessionTime, $dbModuleId);

     $sessionqrystmt->store_result();

    $sessionnum = $sessionqrystmt->num_rows();   

        $dataArraySession = array();

 while ( $sessionqrystmt->fetch() ) { 

     $dataArraySession[$dbModuleId]['Sessions'][$dbSessionId]['SessionDate'] = $dbSesisonDate['SessionTime'] = $dbSessionTime; 

    }

    foreach ($dataArraySession as $sessionId => $sessionData) {

       $sessionHTML = ""; 
       $sessionHTML .= '<select name="session" id="sessionsDrop">'.PHP_EOL;
       $sessionHTML .= '<option value="">Please Select</option>'.PHP_EOL;           
       $sessionHTML .= "<option value='$sessionId'>" . $sessionId . " - " . $sessionData['SessionDate']. " - " . $sessionData['SessionTime'] ."</option>".PHP_EOL;        
       $sessionHTML .= '</select>';
            }


     if ($sessionnum > 0) {

 ?>

         <form action="<?php echo htmlentities($_SERVER['PHP_SELF']); ?>" method="post">
         <p>Sessions: <?php echo $sessionHTML; ?><input id="sessionSubmit" type="submit" value="Submit" name="sesionsubmit" /></p>      
        </form>       

<?php

    }

    else {
   echo "<p>Sorry, You have No Sessions under this Module</p>";
}


}


        ?>

应用程序链接位于：Application

2 个答案:

答案 0 :(得分：1)

我在这里看到一个拼写错误（第111行）：

$dataArraySession[$dbSessionId]['Sessions']['SessionDate'] = $dbSesisonDate['SessionTime'] = $dbSesisonTime;

您绑定的参数名为$dbSessionTime，您正在为$dbSesisonTime数组分配$dataArraySession。这将导致$dataArraySession不被第109行的while循环中的任何值填充。随后，第115行中的foreach循环将永远不会被执行，因为$sessionHTML在此循环内定义，在第131行

中使用它时，将在以后定义

PS：您提供的应用程序链接需要进行身份验证才能继续。

编辑，以便在特定courseId没有数据的情况下提供代码示例：

在130-132语句中包装行if，以确保只有在找到某些结果时才会显示下拉列表

if ($sessionnum > 0) {
   // display your form
}
else {
   echo "No results found!";
}

答案 1 :(得分：0)

更改$sessionHTML .= '<select name="session" id="sessionsDrop">'.PHP_EOL;

至$sessionHTML .= '<select name="sessionsDrop" id="sessionsDrop">'.PHP_EOL;

在POST中传递的名称不是id 

<?php

     // connect to the database
 include('connect.php');

 /* check connection */
 if (mysqli_connect_errno()) {
printf("Connect failed: %s\n", mysqli_connect_error());
die();
}

 $courseid = (isset($_POST['courseid'])) ? $_POST['courseid'] : '';

?>

   <h1>DELETING AN ASSESSMENT</h1>

    <form action="<?php echo htmlentities($_SERVER['PHP_SELF']); ?>" method="post">
     <p>Course ID: <input type="text" name="courseid" /><input id="courseSubmit" type="submit" value="Submit" name="submit" /></p>      
    </form>


    <?php
  if (isset($_POST['submit'])) {

    $query = "
             SELECT cm.CourseId, cm.ModuleId, 
             c.CourseName,
             m.ModuleName
             FROM Course c
             INNER JOIN Course_Module cm ON c.CourseId = cm.CourseId
             JOIN Module m ON cm.ModuleId = m.ModuleId
             WHERE
             (c.CourseId = ?)
             ORDER BY c.CourseName, m.ModuleId
            ";

$qrystmt=$mysqli->prepare($query);
// You only need to call bind_param once
$qrystmt->bind_param("s",$courseid);
// get result and assign variables (prefix with db)

$qrystmt->execute(); 

$qrystmt->bind_result($dbCourseId,$dbModuleId,$dbCourseName,$dbModuleName);

 $qrystmt->store_result();

$num = $qrystmt->num_rows();

if($num ==0){
    echo "<p>Sorry, No Course was found with this Course ID '$courseid'</p>";
} else { 

    $dataArray = array();

 while ( $qrystmt->fetch() ) { 
      // data array
      $dataArray[$dbCourseId]['CourseName'] = $dbCourseName; 
      $dataArray[$dbCourseId]['Modules'][$dbModuleId]['ModuleName'] = $dbModuleName; 
       // session data
      $_SESSION['idcourse'] = $dbCourseId;
      $_SESSION['namecourse'] = $dbCourseName;

}

 foreach ($dataArray as $courseId => $courseData) {

      $output = ""; 

      $output .= "<p><strong>Course:</strong> " . $courseId .  " - "  . $courseData['CourseName'] . "</p>";

   $moduleHTML = ""; 
   $moduleHTML .= '<select name="modulesDrop" id="modulesDrop">'.PHP_EOL;
   $moduleHTML .= '<option value="">Please Select</option>'.PHP_EOL;      
        foreach ($courseData['Modules'] as $moduleId => $moduleData) {        

        $moduleHTML .= "<option value='$moduleId'>" . $moduleId . " - " .   
    $moduleData['ModuleName'] ."</option>".PHP_EOL;        
  } 
        }
        $moduleHTML .= '</select>';

  echo $output;

    }


    ?>

     <form action="<?php echo htmlentities($_SERVER['PHP_SELF']); ?>" method="post">
     <p>Module: <?php echo $moduleHTML; ?><input id="moduleSubmit" type="submit" value="Submit" name="modulesubmit" /></p>      
    </form> 



    <?php

}

 if (isset($_POST['modulesubmit'])) {

 var_dump($_POST['modulesDrop']);

        $sessionquery = "
             SELECT SessionId, SessionDate, SessionTime, ModuleId
             FROM Session
             WHERE
             (ModuleId = ?)
             ORDER BY SessionDate, SessionTime 
            ";

$sessionqrystmt=$mysqli->prepare($sessionquery);
// You only need to call bind_param once
$sessionqrystmt->bind_param("s",$_POST['modulesDrop']);
// get result and assign variables (prefix with db)

$sessionqrystmt->execute(); 

$sessionqrystmt->bind_result($dbSessionId,$dbSessionDate,$dbSessionTime, $dbModuleId);

 $sessionqrystmt->store_result();

$sessionnum = $sessionqrystmt->num_rows();   

    $dataArraySession = array();

 while ( $sessionqrystmt->fetch() ) { 

 $dataArraySession[$dbSessionId]['SessionDate'] = $dbSessionDate;  
 $dataArraySession[$dbSessionId]['SessionTime'] = $dbSessionTime;



}

foreach ($dataArraySession as $sessionId => $sessionData) {

   $sessionHTML = ""; 
   $sessionHTML .= '<select name="session" id="sessionsDrop">'.PHP_EOL;
   $sessionHTML .= '<option value="">Please Select</option>'.PHP_EOL;           
   $sessionHTML .= "<option value='$sessionId'>" . $sessionId . " - " . $sessionData['SessionDate']. " - " . $sessionData['SessionTime'] ."</option>".PHP_EOL;        
   $sessionHTML .= '</select>';
        }


 if ($sessionnum > 0) {

 ?>

     <form action="<?php echo htmlentities($_SERVER['PHP_SELF']); ?>" method="post">
     <p>Sessions: <?php echo $sessionHTML; ?><input id="sessionSubmit" type="submit" value="Submit" name="sesionsubmit" /></p>      
    </form>       

<?php

}

else {
 echo "<p>Sorry, You have No Sessions under this Module</p>";
}


}


    ?>
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