Hi everyone,
I've read through the FAQs for Dynamic Dropdown Menus on this site, as well as others, and I can't figure out why my code won't work. I have two dropdown boxes that need to be populated with data from a mysql table; one menu for route types, and one for route numbers. When I choose the route from the 'Route' menu, the 'Number' menu automatically populates with all of the possible numbers, rather than only those that correspond with the route type. I can tell that the problem has something to do with the value of 'Route' not being recognized, but I don't know why. I'm a beginner when it comes to PHP, so any suggestions or help would be much appreciated! Thanks!
The code is as follows:
<html>
<body>
<basefont face='calibri' color='#7E2217'>
<?php
// set variables
$mileTable = $_GET['mileTable'];
$routeType = isset($_POST['Roadtype'])? $_POST['Roadtype']: 0;
include 'opendbMile.php';
include 'error.php';
// Connect to the MySQL DBMS
if (!($connection = @ mysql_connect($hostName,
$username,
$password)))
die("Could not connect");
if (!mysql_select_db($databaseName, $connection))
showerror( );
// Start a query...
$query = "SELECT ID,
Roadtype
FROM Alabama
GROUP BY Roadtype";
// execute the SQL statement
$result = mysql_query($query, $connection) or die(mysql_error());
echo '<form name="mileform" method="post" action="MileQuery.php">';
echo '<p>Route:
<select name="routeType" id="routeType" onchange="this.form.submit();">
<option value="0"'.($routeType == 0? ' SELECTED': '').'>Route</option>';
while($row = mysql_fetch_array($result)){
echo '
<option value="'.$row[0].'"'.(($routeType == $row[0])? ' SELECTED': '').'>'.$row[1].'</option>';
}
echo '
</select>
</p>';
// create the SQL statement
$query2 = "SELECT ID,
Roadnumber
FROM Alabama
GROUP BY Roadnumber";
if($mnucategory != 0){ // Filter road numbers
$query2 .= " WHERE Roadtype='".$routeType."'";
}
// execute the SQL statement
$result2 = mysql_query($query2, $connection) or die(mysql_error());
echo '<p>Number:
<select name="routeNumber" id="routeNumber" onchange="this.form.submit();">
<option value="0"'.($routeNumber == 0? ' SELECTED': '').'>Number</option>';
while($row2 = mysql_fetch_array($result2)){
echo '
<option value="', $row2[0].'"'.(($routeNumber == $row2[0])? ' SELECTED': '').'>'. $row2[1], '</option>';
}
echo '
</select>
</p>';
// Close the DBMS connection
mysql_close($connection);
?>
</form>
</body>
</html>
