dynamic dropdown

[marke1415]

can someone please check my code?

i have:
category_lib ->(table)
- category_code------- name ->(fields)
-- 001----------------processor
-- 002----------------motherboard
-- 003----------------hard disk

subcategory_lib ->(table)
- subcategory_code----subcategory_name ->(fields)
-- 001---------------- Athlon XP
-- 001---------------- Athlon 64
-- 001---------------- Intel
-- 002---------------- Asus
-- 002---------------- Epox
-- 002---------------- MSI
-- 003---------------- Seagate
-- 003---------------- Maxtor

what i wanted to do is to popuplate the 1st combobox with category_lib and populate the 2nd combobox with subcategory_lib filtered depending on what he chooses in the 1st combobox.

thanks

here is my code:

<?php

$dbcnx = @mysql_connect('localhost','root','');
if (!$dbcnx) {
	exit('<p>Unable to connect to the server</p>');
}
else echo '<p> Server Connected </p>' ;

if (!@mysql_select_db('main')){
	exit('<p>Unable to connect to the database</p>');
}
else echo '<p> Database Connected </p>' ;

$result_cat = @mysql_query('select * from category_lib');
if (!$result_cat) {
	exit('<p>Error performing query' . mysql_error() .'</p>');
}
?>
<form action="" method="post" enctype="multipart/form-data" name="form1">
      <select name="cats" size="1">
        <option selected value="">Category Listings</option>
        <?PHP
	while ($category = mysql_fetch_array($result_cat)){
		$catid =$category['CATEGORY_CODE'];
		$catname =$category['NAME'];
		echo "<option value='$cats'>$catname</option>\n";
	}
	?>
      </select>
</form>		
<?php
	$sql = "CREATE TEMPORARY TABLE cat1 AS SELECT DISTINCT category_code, name FROM category_lib";  

	if (!$sql) {
		exit('<p>Unable to Create Temporary Table</p>');
	}
	else echo '<p> Table Created </p>' ;

$sql = "INSERT INTO cat1 SELECT DISTINCT subcategory_code, subcategory_name FROM subcategory_lib";  
if (!$sql) {
	exit('<p>Unable to Insert</p>');
}
else echo '<p> Inserted </p>' ;

$sqlres = "SELECT DISTINCT * FROM cat1";  
if (!$sql) {
	exit('<p>Unable to Select from cat1</p>');
}
else echo '<p> Items Selected </p>' ;


echo '<select name="category">';
while ($row = mysql_fetch_assoc($sqlres))
	$catid =$row['CATEGORY_CODE'];
	{   
	echo '<option value="'.$row[$catid].'">', '</option>'; 
	}
?>
</select>

[Drakla]

Well you're not actually running any of the queries in the bottom half.

You define the SQL statements for them, but there are no mysql_query statements to go with them.

[marke1415]

thanks, but what will i add? how? and where am i going to put it?sorry but im just a newbie in php

[bpat1434]

I think that the best bet is to grab all the pairs you can in arrays, and populate the drop-downs via JavaScript.

If you search google, you'll find a bunch of tutorials. This is a fairly common question.

~Brett

[jefainer]

Another solution is to and an onchange statment to the first dropdown that will reexecute the application populating the next dropdown with the filtered information. i.e.

// the first dropdown box you will populate on first execution leaving the default record null. This way the second dropdown is default empty.

$CSdbBld = $db->getCol("SELECT DISTINCT BuildingName FROM closet ORDER by BuildingName");

		if ($CSdbBld == null) {

			$CSdbmessage = "<h1>Record not found</h1>";
		}

		echo "<TR><TH bgcolor='#EEEEEE' class='FormLabel'>Building Name <I><SMALL>(building)</SMALL></i>";

		//first dropdown  starts here

					$alen = count($CSdbBld);

When defining Option Group, add in a onchange statement. The example uses javascript to reload the page. I could not find a way to do this with PHP.
echo "<SELECT name='building' onchange=\"this.form.submit();\">";
echo "<OPTGROUP label='Building Name'>";

					echo "<OPTION value=''> </OPTION>";

					for($i=0; $i <= $alen - 1; $i++){

						if ($CSdbBld[$i] == $building) {

							echo "<OPTION selected value='$CSdbBld[$i]'> $CSdbBld[$i]</OPTION>";

						}else {

							echo "<OPTION value='$CSdbBld[$i]'> $CSdbBld[$i]</OPTION>";

						}
					}

				 	echo "</OPTGROUP>";
					echo "</SELECT>";

		//Test end

The second dropdown will auto fill based on the value of the first. Once the first is set the application will re-run and populate the second.

		echo "</TH>";


		$CSdbCl = $db->getCol("SELECT DISTINCT ClosetNumber FROM closet 
								WHERE closet.BuildingName ='$building' ORDER by ClosetNumber");

		if ($CSdbCl == null) {

				$CSdbmessage = "<h1>Record not found</h1>";
		}			

		echo "<TH bgcolor='#EEEEEE' class='FormLabel'>Closet Number <I><SMALL>(closet)</SMALL></i>)";

I just created a function to do the dropdown. The code is the same as the one above.
DropDown($CSdbCl, "closet", $closet, "Closet Number");

[KevinUK]

Hello,

It's my first post here, and I'm also stuck wth a similar issue. Here's the code I'm using:

[SQL processing already done, no need to add this in the thread]


echo '<form name=\"form1\" method=\"post\" action=\"\">';
echo '<select name=\"select\">';

while($row = mysql_fetch_array( $sql ))
{
echo "<option value=\"$row['domain_name']\">" .$row['domain_name'] .'</option>';
}

echo '</form>';

The main problem I have is that when this code is executed, the error that's returned is:

Parse error: parse error, unexpected T_ENCAPSED_AND_WHITESPACE, expecting T_STRING or T_VARIABLE or T_NUM_STRING

I've ascertained that the problem lies with the <option value> tag, this works fine (albeit the value is "Array" (literally)):

echo "<option value=\"$row\">" .$row['domain_name'] .'</option>';

I'll ask my question now 🙂

How can I escape the ['domain_name'] part in the <option value> tag. It's essential that the form ends up looking something similar to this:

<option value="abc.com">abc.com</option>
<option value="123.com">123.com</option>

Apologies in advance if this is a bit long-winded, I wanted to ensure that I supplied as much information as is required.

Thanks for reading.

Kevin

[KevinUK]

I'm not entirely sure how this works:

You spend what seems like hours trying to resolve a relatively simple problem, you get more and more frustrated, until you finally ask for help.

You go and get a coffee, and then a different approach suddenly hits you - and - it works 🙂

echo '<option value=' .$row['domain_name'] .'>' .$row['domain_name'] .'</option>';

Kevin