我的应用程序发生了一些奇怪的事情。下面是我的代码,其中用户在文本输入中输入 courseid 并提交文本输入。如果它从数据库中找到课程,则显示找到课程的回声,否则表明课程未找到。现在这适用于所有浏览器(IE、Opera、Safari、Firefox 和 Chrome)。下面是这个的代码:
<h1>CREATING A NEW ASSESSMENT</h1>
<form action="<?php echo htmlentities($_SERVER['PHP_SELF']); ?>" method="post">
<p>Course ID: <input type="text" name="courseid" /><input id="courseSubmit" type="submit" value="Submit" name="submit" /></p> <!-- Enter User Id here-->
</form>
<?php
if (isset($_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 '$courseid'</p>";
} else {
echo "<p>Course Found: '$courseid'</p>";
}
但现在我决定更改设置,因此他们可以从下拉菜单中选择课程 ID,而不是在文本输入中输入 courseID。所以我把代码改成下面这样:
$sql = "SELECT CourseId, CourseName FROM Course";
$sqlstmt=$mysqli->prepare($sql);
$sqlstmt->execute();
$sqlstmt->bind_result($dbCourseId, $dbCourseName);
$courses = array(); // easier if you don't use generic names for data
$courseHTML = "";
$courseHTML .= '<select name="courses" id="coursesDrop">'.PHP_EOL;
$courseHTML .= '<option value="">Please Select</option>'.PHP_EOL;
while($sqlstmt->fetch())
{
$course = $dbCourseId;
$coursename = $dbCourseName;
$courseHTML .= "<option value='".$course."'>" . $course . " - " . $coursename . "</option>".PHP_EOL;
}
$courseHTML .= '</select>';
$courseHTML .= '</form>';
?>
<h1>CREATING A NEW ASSESSMENT</h1>
<form action="<?php echo htmlentities($_SERVER['PHP_SELF']); ?>" method="post">
<table>
<tr>
<th>Course: <?php echo $courseHTML; ?><input id="courseSubmit" type="submit" value="Submit" name="submit" /></th>
</tr>
</table>
</form>
<?php
if (isset($_POST['submit'])) {
$submittedCourseId = $_POST['courses'];
$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
$qrystmt->bind_param("s",$submittedCourseId);
// 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 style='color: red'>Please Select a Course</p>";
} else {
echo "<p style='color: green'>Course Found '$courseid'</p>";
}
但这很奇怪,下拉菜单在 Chrome、Firefox 和 Safari 中有效,但在 Opera 和 IE 中无效。那么我的问题是,第二个代码块中有什么东西阻止它在 IE 或 Opera 中工作吗?