我在寻找下列情况下相互关联的下拉列表：
如果选择学位，那么它只会显示具有该学位的大学，在选择大学后，它只显示大学有校区的城市。
现在选择了所有列表后，我想将答案保存在新表中，但无法这样做。文件附在下面。
的index.php
<?php
$con = mysql_connect('localhost', 'root', '');
if (!$con) {
die('Could not connect: ' . mysql_error());
}
mysql_select_db('commonapp');
$query="SELECT * FROM degree";
$result=mysql_query($query);
?>
<html>
<head>
<title>Registration Form</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<script language="javascript" type="text/javascript">
function getXMLHTTP() { //fuction to return the xml http object
var xmlhttp=false;
try{
xmlhttp=new XMLHttpRequest();
}
catch(e) {
try{
xmlhttp= new ActiveXObject("Microsoft.XMLHTTP");
}
catch(e){
try{
xmlhttp = new ActiveXObject("Msxml2.XMLHTTP");
}
catch(e1){
xmlhttp=false;
}
}
}
return xmlhttp;
}
function getState(degreeId) {
var strURL="findUniversity.php?degree="+degreeId;
var req = getXMLHTTP();
if (req) {
req.onreadystatechange = function() {
if (req.readyState == 4) {
// only if "OK"
if (req.status == 200) {
document.getElementById('statediv').innerHTML=req.responseText;
document.getElementById('citydiv').innerHTML='<select name="city">'+
'<option>Select City</option>'+
'</select>';
} else {
alert("Problem while using XMLHTTP:\n" + req.statusText);
}
}
}
req.open("GET", strURL, true);
req.send(null);
}
}
function getCity(degreeId,universityId) {
var strURL="findCity.php?degree="+degreeId+"&uniid="+universityId;
var req = getXMLHTTP();
if (req) {
req.onreadystatechange = function() {
if (req.readyState == 4) {
// only if "OK"
if (req.status == 200) {
document.getElementById('citydiv').innerHTML=req.responseText;
} else {
alert("Problem while using XMLHTTP:\n" + req.statusText);
}
}
}
req.open("GET", strURL, true);
req.send(null);
}
}
</script>
<style type="text/css">
body {font-family: Arial, "Trebuchet MS";font-size: 17px;color: #52B6EB; }
a{font-weight: bold;letter-spacing: -1px;color: #52B6EB;text-decoration:none;}
a:hover{color: #99A607;text-decoration:underline;}
#top{width:43%;margin-top: 25px; height:60px; border:1px solid #BBBBBB; padding:10px;}
#tutorialHead{width:43%;margin-top: 12px; height:30px; border:1px solid #BBBBBB; padding:11px;}
.tutorialTitle{width:95%;float:left;color:#99A607}
.tutorialTitle a{float:right;margin-left:20px;}
.tutorialLink{float:right;}
table
{
margin-top:70px;
border: 1px solid #BBBBBB;
padding:25px;
height: 35px;
}
</style>
</head>
<body>
<form method="post" action="admForm.php" name="form1">
<center>
<table width="45%" cellspacing="0" cellpadding="0">
<tr>
<td width="75">Degree</td>
<td width="50">:</td>
<td width="150">
<select name="degree" onChange="getState(this.value)">
<option value="">Select Degree</option>
<?php while ($row=mysql_fetch_array($result)) { ?>
<option value=<?php echo $row['id']?>><?php echo $row['degree']?></option>
<?php } ?>
</select>
</td>
</tr>
<tr style="">
<td>University</td>
<td width="50">:</td>
<td ><div id="statediv">
<select name="university" >
<option>Select University</option>
</select></div></td>
</tr>
<tr style="">
<td>City</td>
<td width="50">:</td>
<td ><div id="citydiv">
<select name="city" type="text">
<option>City</option>
</select></div></td>
</tr>
<tr>
<td>
<input class="buttom" name="Submit" value="Submit" type="submit">
</td>
</tr>
</table>
</center>
</form>
</body>
</html>
findUniversity
<?php $degree=intval($_GET['degree']);
$con = mysql_connect('localhost', 'root', '');
if (!$con) {
die('Could not connect: ' . mysql_error());
}
mysql_select_db('commonapp');
$query="SELECT id,uniname FROM uni WHERE degreeid='$degree'";
$result=mysql_query($query);
?>
<select name="university" onchange="getCity(<?php echo $degree?>,this.value)">
<option>Select University</option>
<?php while ($row=mysql_fetch_array($result)) { ?>
<option value=<?php echo $row['id']?>><?php echo $row['uniname']?></option>
<?php } ?>
findCity.php
<?php $degreeId=intval($_GET['degree']);
$universityId=intval($_GET['uniid']);
$con = mysql_connect('localhost', 'root', '');
if (!$con) {
die('Could not connect: ' . mysql_error());
}
mysql_select_db('commonapp');
$query="SELECT id,city FROM city WHERE degreeid='$degreeId' AND uniid='$universityId'";
$result=mysql_query($query);
?>
<select name="city">
<option>Select City</option>
<?php while($row=mysql_fetch_array($result)) { ?>
<option value><?php echo $row['city']?></option>
<?php } ?>
</select>