[HELP] Dynamic Dependent Select Boxes

[DrWho4]

Brand new to the forum, and have only been working with HTML, PHP, & MySQL for about 3 months.

 

I've run into an issue I can't seem to figure out how to work around. I want to have two select boxes, that are dependent on one another.

 

For Example:

 

First box lists types of games:

 

RPG

LARP

Board Game

Miniatures

CCG

 

The second box displays game names of the type selected above.

 

I have a MySQL table setup for the second box. To be honest I kinda already have it working... with one small but MAJOR glitch.

 

I select the first box and the page submits using onchange='this.form.submit()'. When the page reloads the first select box reverts back to it's default setting, but the second box does correctly filter & show the content based on the selection that was made in the first box.

 

My Question:

 

How do I set this up so that the first box displays the user selected setting while also passing the $_POST information to the second box?

 

My Code:

 

<table>

<tr>

<td width=50%>

Game Type:

</td>

<td width=50%>

<form name='game_type' action='event_submit.php' method='post'>

<select name='game_type' align=center onchange='this.form.submit()' style="width:150px;margin:5px 0 5px 0;">

<option value=''>Chose a Game Type</option>

<option value='RPG'>RPG</option>

<option value='LARP'>LARP</option>

<option value='Board Game'>Board Game</option>

<option value='CCG'>Collectable Cards & Games</option>

<option value='Miniatures'>Miniatures</option>

</select>

</form>

</td>

</tr>

<tr>

<td width=50%>

Game System:

</td>

<td width=50%>

 

<?php

 

 

$game_type = $_POST['game_type'];

 

echo "$game_type";

 

if (!$con)

  {

  die('Could not connect: ' . mysql_error());

  }

 

mysql_select_db("DrowCon", $con);

 

$result = mysql_query("SELECT * FROM Games WHERE Type='$game_type' ORDER BY System ASC");

 

 

 

    echo "<form name='game_system' action='event_submit_form.php' method='post'>";

echo "<select name='game_system' align=center style='width:150px;margin:5px 0 5px 0;'>";

echo "<option value=''>Chose a Game System</option>";

while($row_game = mysql_fetch_array($result))

  {

  echo "<option value=''>".$row_game['System']."</option>";

  }

echo "</form>";

 

 

mysql_close($con);

?>

</td>

</tr>

</table>