&lt;select&gt; problem

<select> problem

lastuser

Hi everyone!

I have a big problem (for me) with select box. I want make like this

select 1
1
2
3

And when you select for example number 2 script will get automatic select 2 information from mysql. Now number 2 is first selected so it can be bold. Select 2 values depends on about what you selected in select 1.

select 2
1
2
3

This is pretty hard to explain but I hope that someone understand what I mean. I have no idea how to do this. I only know that it needs little bit javascript (sending automatic select value).

nnichols

OK. I'll have a go at explaining this one.

Lets assume that you have your first select built as follows -

$sel1 = "Select 1:<SELECT name=\"sel_name_1\" onChange=\"this.submit()\">";
$sel1 .= "<OPTION value=\"1\">1</OPTION>";
$sel1 .= "<OPTION value=\"2\">2</OPTION>";
$sel1 .= "<OPTION value=\"3\">3</OPTION>";
$sel1 .= "</SELECT>";

You need the FORM ACTION to point to itself -

$output = "<FORM name=\"multi_selects\" method=\"POST\" action=\"$PHP_SELF\">";

If you have no value for $sel_name_1 when the page loads the second select will be empty -

if (!$_POST['sel_name_1']) {
    $sel2 = "Select 2:<SELECT name=sel_name_2>";
    $sel2 .= "<OPTION value=\"\">&nbsp;</OPTION>";
    $sel2 .= "</SELECT>";
    }

if there is a value for $sel_name_1 you retrive the data for the second select -

else {
    $sel2 = "Select 2:<SELECT name=sel_name_2>";
    // do query to find data to build second select
    // you then loop through the query results to build the data for the select
    $result = ;// do your query
    while ($row=mysql_fetch_array($result)) {
        $sel2 .= '<OPTION value="' . $row['value'] . '">' . $row['text'] . '</OPTION>";
        }
    $sel2 .= "</SELECT>";

S**t. I've got to go now. I hope you can get the idea. I will post an example to go with this later on in the day.

Hope this helps 😉

lastuser

Thanks for the helping! I tried to do that, but I couldn't get this.submit working. It alwas gave me error. I would be appreciate if you have time to give a example!

I tried to get it work like this. What is wrong??

<form action="<?php print("".$_SERVER['PHP_SELF'].""); ?>" method="post" name="selects">
	<select name="sel_name_1" onChange="this.submit();">
	 <option value="1">Test</option>
	 <option value="2">Test2</option>
	 <option value="3">Test3</option>
      </select>
	  </form>

Okay I get it works when I replace this.submit -> submit . Why this.submit does not works??

nnichols

Sorry about that - it should be "this.form.submit()".

Will post full example in a bit.

nnichols

It's not the most beautiful piece of code, but it demonstrates what you are trying to do. It does work. Normally I encapsulate the code that builds the select objects in a function.

<?PHP

/*
Assume a database structure as below

Table categories

|----------|-------------|
|  CAT_ID  |   CAT_NAME  |
|----------|-------------|
|    1     |    cars     |
|    2     | motorcycles |
|    3     | aeroplanes  |
|----------|-------------|

Table items

|----------|-------------|--------------|
| ITEM_ID  |  ITEM_NAME  |   CAT_ID     |
|----------|-------------|--------------|
|    1     |   ford      |       1      |
|    2     |   lotus     |       1      |
|    3     |   jaguar    |       1      |
|    4     |   triumph   |       2      |
|    5     |   ducati    |       2      |
|    6     |   honda     |       2      |
|    7     |   cessna    |       3      |
|    8     |   piper     |       3      |
|    9     |   warrior   |       3      |
|----------|-------------|--------------|

*/

$db = mysql_pconnect('server','uname','pwd') or die('Could not connect to db server');  //connect to your database
mysql_select_db('db') or die('Could not select db');

$output = "<FORM name=\"multi_selects\" method=\"POST\" action=\"$PHP_SELF\">";

$sel1 = "Select 1:<SELECT name=\"sel_name_1\" onChange=\"this.form.submit()\">";

$sql = "SELECT * FROM categories";
$result = mysql_query($sql);
while ($row = mysql_fetch_array($result)) {
	if ($_POST['sel_name_1'] == $row['CAT_ID']) { //this selects the correct option when doing the reload
		$selected = ' SELECTED';
		}
	else {
		$selected = '';
		}
	$sel1 .= '<OPTION' . $selected . ' value="' . $row['CAT_ID'] . '">' . $row['CAT_NAME'] . '</OPTION>';
	}
$sel1 .= "</SELECT>";

$output .= $sel1;

/* ------------------------------------------------------------------------------------------------------- */

if (!isset($_POST['sel_name_1'])) {
	$sel2 = "Select 2:<SELECT name=sel_name_2>";
	$sel2 .= "<OPTION value=\"\">&nbsp;</OPTION>";
	$sel2 .= "</SELECT>";
	}

else {
	$sel2 = "Select 2:<SELECT name=sel_name_2>";
	// do query to find data to build second select
	$sql = "SELECT * FROM items WHERE CAT_ID=" . $_POST['sel_name_1'];
	$result = mysql_query($sql);

// you then loop through the query results to build the data for the select
while ($row=mysql_fetch_array($result)) {
	$sel2 .= '<OPTION value="' . $row['ITEM_ID'] . '">' . $row['ITEM_NAME'] . '</OPTION>';
	}
$sel2 .= "</SELECT>";
}
$output .= $sel2;
$output .= "</FORM>";
echo $output;

?>

Hope this helps 😉

lastuser

I want to tell very big thanks to you! If in this world would more people like you this world would great place to live! =)