我想当用户选择时显示下拉菜单中的所有问题All从问题下拉菜单中并将其输出在下面。问题是它没有这样做，更糟糕的是，它给了我未定义的偏移错误，指出：
Notice: Undefined offset: ... in .... on line 605
605行是：
echo '<p><strong>Question:</strong> ' .htmlspecialchars($arrQuestionNo[$key]). ': ' .htmlspecialchars($arrQuestionContent[$key]). '</p>' . PHP_EOL;
我的问题是如何修复错误并在用户选择时显示所有问题All option?
我有一个演示你可以看一下：DEMO http://helios.hud.ac.uk/u0867587/Mobile_app/Text29.php
请按照以下步骤操作：
- 在模块下拉菜单中，选择系统策略并提交
- 当评估下拉菜单出现时，选择 POKUB1 并提交
- 您将看到学生和问题下拉菜单。如果您打开下拉菜单，您可以看到有 3 个学生和 2 个问题。请选择一名学生并
All提问并提交。当我真的想在此处显示问题的所有详细信息时，您将在此处看到错误。
CODE:
问题下拉菜单：
<select name="question" id="questionsDrop">
<option value="0">All</option>
<option value=23">1</option>
<option value=32">1</option>
</select>
下面的代码根据从问题下拉菜单中选择的选项来确定显示。
function StudentAnswers()
{
$selectedstudentanswerqry = "
SELECT
sa.StudentId, StudentAlias, StudentForename, StudentSurname, q.SessionId,
QuestionNo, QuestionContent, o.OptionType, q.NoofAnswers,
GROUP_CONCAT( DISTINCT Answer ORDER BY Answer SEPARATOR ',' ) AS Answer, r.ReplyType, QuestionMarks,
GROUP_CONCAT(DISTINCT StudentAnswer ORDER BY StudentAnswer SEPARATOR ',') AS StudentAnswer, ResponseTime, MouseClick, StudentMark
FROM Student st
INNER JOIN Student_Answer sa ON (st.StudentId = sa.StudentId)
INNER JOIN Student_Response sr ON (sa.StudentId = sr.StudentId)
INNER JOIN Question q ON (sa.QuestionId = q.QuestionId)
INNER JOIN Answer an ON q.QuestionId = an.QuestionId
LEFT JOIN Reply r ON q.ReplyId = r.ReplyId
LEFT JOIN Option_Table o ON q.OptionId = o.OptionId
";
// Initially empty
$where = array('q.SessionId = ?');
$parameters = array($_POST["session"]);
$parameterTypes = 'i';
// Check whether a specific question was selected
$p_question = empty($_POST["question"])?'':$_POST["question"];
switch($p_question){
case 0:
//dont' add where filters
break;
default:
$where[] = 'q.QuestionId = ?';
$parameters[] .= $_POST["question"];
$parameterTypes .= 'i';
}
// If we added to $where in any of the conditionals, we need a WHERE clause in
// our query
if(!empty($where)) {
$selectedstudentanswerqry .= ' WHERE ' . implode(' AND ', $where);
global $mysqli;
$selectedstudentanswerstmt=$mysqli->prepare($selectedstudentanswerqry);
// You only need to call bind_param once
if (count($where) == 1) {
$selectedstudentanswerstmt->bind_param($parameterTypes, $parameters[0]);
}
else if (count($where) == 2) {
$selectedstudentanswerstmt->bind_param($parameterTypes, $parameters[0], $parameters[1]);
}
}
$selectedstudentanswerqry .= "
GROUP BY sa.StudentId, q.QuestionId
ORDER BY StudentAlias, q.SessionId, QuestionNo
";
// get result and assign variables (prefix with db)
$selectedstudentanswerstmt->execute();
$selectedstudentanswerstmt->bind_result($detailsStudentId,$detailsStudentAlias,$detailsStudentForename,$detailsStudentSurname,$detailsSessionId,$detailsQuestionNo,
$detailsQuestionContent,$detailsOptionType,$detailsNoofAnswers,$detailsAnswer,$detailsReplyType,$detailsQuestionMarks,$detailsStudentAnswer,$detailsResponseTime,
$detailsMouseClick,$detailsStudentMark);
$selectedstudentanswerstmt->store_result();
$selectedstudentanswernum = $selectedstudentanswerstmt->num_rows();
$question = array();
while ($selectedstudentanswerstmt->fetch()) {
$arrQuestionNo = array();
$arrQuestionContent = array();
$arrQuestionNo[ $detailsStudentId ] = $detailsQuestionNo;
$arrQuestionContent[ $detailsStudentId ] = $detailsQuestionContent;
$questions[] = $arrQuestionNo;
$questions[] = $arrQuestionContent;
}
$selectedstudentanswerstmt->close();
?>
...........................................................................................
<h2>STUDENT'S ANSWERS</h2>
<?php
foreach ($questions as $key=>$question) {
echo '<p><strong>Question:</strong> ' .htmlspecialchars($arrQuestionNo[$key]). ': ' .htmlspecialchars($arrQuestionContent[$key]). '</p>' . PHP_EOL;
}
}
?>
UPDATE:
学生表结构：
CREATE TABLE `Student` (
`StudentId` int(10) NOT NULL AUTO_INCREMENT,
`StudentForename` varchar(25) NOT NULL,
`StudentSurname` varchar(25) NOT NULL,
`StudentAlias` varchar(15) NOT NULL,
`StudentEmail` varchar(50) NOT NULL,
`StudentUsername` varchar(20) NOT NULL,
`StudentPassword` varchar(50) NOT NULL,
`StudentDOB` date NOT NULL,
`Year` int(2) NOT NULL,
`CourseId` int(6) NOT NULL,
`Active` tinyint(1) NOT NULL DEFAULT '1',
PRIMARY KEY (`StudentId`),
KEY `FK_Course` (`CourseId`)
) ENGINE=InnoDB AUTO_INCREMENT=41 DEFAULT CHARSET=utf8
问题表结构：
CREATE TABLE `Question` (
`QuestionId` int(10) NOT NULL AUTO_INCREMENT,
`SessionId` int(10) NOT NULL,
`QuestionNo` int(3) NOT NULL,
`QuestionContent` varchar(5000) NOT NULL,
`NoofAnswers` int(2) NOT NULL,
`ReplyId` int(1) NOT NULL,
`QuestionMarks` int(4) NOT NULL,
`OptionId` int(2) NOT NULL,
PRIMARY KEY (`QuestionId`)
) ENGINE=InnoDB AUTO_INCREMENT=357 DEFAULT CHARSET=utf8
