问题
<body>
<div id="wrapper">
<!-- Navigation -->
<nav class="navbar navbar-default navbar-static-top" role="navigation" style="margin-bottom: 0">
<div class="navbar-header">
<button type="button" class="navbar-toggle" data-toggle="collapse" data-target=".navbar-collapse">
<span class="sr-only">Toggle navigation</span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
</button>
<a class="navbar-brand" href="index.php">Student Scheduling System</a>
</div>
<!-- /.navbar-header -->
<div class="navbar-default sidebar" role="navigation">
<div class="sidebar-nav navbar-collapse">
<ul class="nav" id="side-menu">
<li>
<a href="index.php"><i class="fa fa-home fa-fw"></i> Home</a>
</li>
<li>
<a href="student.php"><i class="fa fa-users fa-fw"></i> Student</a>
</li>
<li>
<a href="coourses.php"><i class="fa fa-university fa-fw"></i> Courses</a>
</li>
<li>
<a href="subject.php"><i class="fa fa-archive fa-fw"></i> Subjects</a>
</li>
</ul>
</div>
<!-- /.sidebar-collapse -->
</div>
<!-- /.navbar-static-side -->
</nav>
<!-- Page Content -->
<div id="page-wrapper">
<div class="container-fluid">
<div class="row">
<div class="col-lg-12">
<h3 class="page-header">Student</h3>
<div class="panel panel-primary">
<div class="panel-heading">
Student List
</div>
<!-- /.panel-heading -->
<div class="panel-body">
<div class="table-responsive">
<table class="table table-striped table-hover" id="dataTables-example">
<thead>
<tr>
<th>Student ID</th>
<th>First Name</th>
<th>Last Name</th>
<th>Course</th>
<th>Year</th>
<th>Section</th>
<th>Section ID</th>
</tr>
</thead>
<tbody>
<?php
// Five steps to PHP database connections:
// 1. Create a database connection
// (Use your own servername, username and password if they are different.)
// $connection allows us to keep refering to this connection after it is established
$connection = mysql_connect("localhost","root","");
if (!$connection) {
die("Database connection failed: " . mysql_error());
}
// 2. Select a database to use
$db_select = mysql_select_db("studsystem",$connection);
if (!$db_select) {
die("Database selection failed: " . mysql_error());
}
?>
<?php
$result = mysql_query("Select tbl_course.studno, tbl_course.studfname, tbl_course.studlname,
tbl_coursetype.course_desc, tblyear.YearName, tblset.setname, tblset.ID
from tbl_course, tbl_coursetype, tblyear, tblset
where tbl_coursetype.course_no=tbl_course.studcourse
AND tblyear.ID=tbl_course.studyear
AND tblset.ID=tbl_course.studset", $connection);
if (!$result) {
die("Database query failed: " . mysql_error());
}
// 4. Use returned data
while ($row = mysql_fetch_array($result)) {
echo "<tr class=\"success\">";
echo "<td>".$row[0]."</td>";
echo "<td>".$row[1]."</td>";
echo "<td>".$row[2]."</td>";
echo "<td>".$row[3]."</td>";
echo "<td>".$row[4]."</td>";
echo "<td>".$row[5]."</td>";
echo "<td>".$row[6]."</td>";
echo "<td><a href=\"viewsubject.php?cours={$row[3]}&year={$row[4]}&set={$row[5]}§ion={$row[6]}\" class=\"btn btn-info btn-xs\">View Subject</a></td>";
echo "<td><a href=\"update_stud.php?studno={$row[0]}&studfname={$row[1]}&studlname={$row[2]}&studcourse={$row[3]}\"><i class=\"fa fa-edit\"></i></a></td>";
echo "<td><a href=\"delete_stud.php?studno={$row[0]}\"><i class=\"fa fa-trash-o\"></i></a></td>";
echo "</tr>";
}
?>
<?php
mysql_close($connection);
?>
</tbody>
</table>
</div>
<!-- /.table-responsive -->
</div>
<!-- /.panel-body -->
</div>
<!-- Button trigger modal -->
<button type="button" class="btn btn-primary" data-toggle="modal" data-target="#myModal">
Add Student
</button>
<!-- Modal -->
<div class="modal fade" id="myModal" tabindex="-1" role="dialog" aria-labelledby="myModalLabel" aria-hidden="true">
<div class="modal-dialog">
<div class="modal-content">
<div class="modal-header">
<button type="button" class="close" data-dismiss="modal" aria-label="Close"><span aria-hidden="true">×</span></button>
<h4 class="modal-title" id="myModalLabel">Add new student</h4>
</div>
<div class="modal-body">
<form role="form" action="save_stud.php" method="post">
<div class="form-group">
<label>First Name</label>
<input type="text" name="studfname" class="form-control" required>
</div>
<div class="form-group">
<label>Last Name</label>
<input type="text" name="studlname" class="form-control" required>
</div>
<div class="form-group">
<label>Student Course</label>
<select name="studcourse" class="form-control">
<?php
// Five steps to PHP database connections:
// 1. Create a database connection
// (Use your own servername, username and password if they are different.)
// $connection allows us to keep refering to this connection after it is established
$connection = mysql_connect("localhost","root","");
if (!$connection) {
die("Database connection failed: " . mysql_error());
}
// 2. Select a database to use
$db_select = mysql_select_db("studsystem",$connection);
if (!$db_select) {
die("Database selection failed: " . mysql_error());
}
?>
<?php
$result = mysql_query("Select setcours, course_desc
from tblset, tbl_coursetype
where tbl_coursetype.course_no=tblset.setcours
group by setcours", $connection);
if (!$result) {
die("Database query failed: " . mysql_error());
}
// 4. Use returned data
while ($row = mysql_fetch_array($result)) {
echo "<option value=\"{$row[0]}\">{$row[1]}</option>";
}
?>
</select>
</div>
<div class="form-group">
<label>Student Year</label>
<select name="studyear" class="form-control">
<?php
// Five steps to PHP database connections:
// 1. Create a database connection
// (Use your own servername, username and password if they are different.)
// $connection allows us to keep refering to this connection after it is established
$connection = mysql_connect("localhost","root","");
if (!$connection) {
die("Database connection failed: " . mysql_error());
}
// 2. Select a database to use
$db_select = mysql_select_db("studsystem",$connection);
if (!$db_select) {
die("Database selection failed: " . mysql_error());
}
?>
<?php
$result = mysql_query("Select setyear, YearName
from tblset, tblyear
where tblyear.ID=tblset.setyear
group by setyear", $connection);
if (!$result) {
die("Database query failed: " . mysql_error());
}
// 4. Use returned data
while ($row = mysql_fetch_array($result)) {
echo "<option value=\"{$row[0]}\">{$row[1]}</option>";
}
?>
</select>
</div>
<div class="form-group">
<label>Section</label>
<select name="studset" class="form-control">
<?php
// Five steps to PHP database connections:
// 1. Create a database connection
// (Use your own servername, username and password if they are different.)
// $connection allows us to keep refering to this connection after it is established
$connection = mysql_connect("localhost","root","");
if (!$connection) {
die("Database connection failed: " . mysql_error());
}
// 2. Select a database to use
$db_select = mysql_select_db("studsystem",$connection);
if (!$db_select) {
die("Database selection failed: " . mysql_error());
}
?>
<?php
$result = mysql_query("SELECT * FROM tblset t LIMIT 0,1000", $connection);
if (!$result) {
die("Database query failed: " . mysql_error());
}
// 4. Use returned data
while ($row = mysql_fetch_array($result)) {
echo "<option value=\"{$row[0]}\">{$row[1]}</option>";
}
?>
</select>
</div>
</div>
<div class="modal-footer">
<button type="button" class="btn btn-default" data-dismiss="modal">Close</button>
<input type="submit" value="Save Changes" class="btn btn-primary" class="form-control">
</div>
</form>
</div>
</div>
</div>
<!--Modal-->
<!-- /.col-lg-12 -->
</div>
<!-- /.row -->
</div>
<!-- /.container-fluid -->
</div>
<!-- /#page-wrapper -->
</div>
<!-- /#wrapper -->
</body>
-Above is the whole code. And below are the screenshots.
I am confused because BSIT has only 1st year level but when everytime I choose BSIT, the second dropdown will also appear 3rd year level, which is 3rd year is only intended for BSED. In short, I want that when everytime I choose a course, it will automatically change the second dropdown menu with its corresponding year level/s. I am sorry for this, but I just want to know if it is possible and how? Please teach me if it is okay with you. Thanks!
回答1:
Like I suggested in the comments, you can use chainedjs for this, or you can create your own function like:
$( document ).ready(function() {
$('#select1').on("change", function(){
var selectedClass = $(this).val(); //store the selected value
$('#select2').val(""); //clear the second dropdown selected value
//now loop through the 2nd dropdown, hide the unwanted options
$('#select2 option').each(function () {
var newValue = $(this).attr('class');
if (selectedClass != newValue && selectedClass != "") {
$(this).hide();
}
else{$(this).show(); }
});
});
});<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.0/jquery.min.js"></script>
<select id="select1">
<option value=""></option>
<option value="number1">number 1</option>
<option value="number2">number 2</option>
</select>
<select id="select2">
<option class=""></option>
<option class="number1">number 1.1</option>
<option class="number2">number 2.1</option>
<option class="number1">number 1.2</option>
<option class="number2">number 2.3</option>
<option class="number1">number 1.3</option>
<option class="number1">number 1.2</option>
</select>来源：https://stackoverflow.com/questions/33079923/how-to-pass-a-php-variable-from-a-dropdown-to-another-dropdown-using-php