Edit with a drop down box...and selected

[Bluelove]

Hi,
i was wondering how i code an option to be selected from a drop down box

In detail :
I want to edit a Product with it's informations, one of the informations is its Category. Categories are stored in another table, so i have a script that shows all those categories in a drop down box (code i use to add a product). When adding a product the corresponding category_id is saved within the product record.

Now i want to edit it, i make a form with all the corresponding info in the Value areas, but how do i make the code for the Option selected? So in the drop down box the category is selected wich corresponds to the category_id saved in the product record?

This is my code to make the drop down box of categories :

$querycat = "SELECT category_id,category FROM category ORDER BY category";
$resultcat = mysql_query($querycat) or die ("DB-fout:".mysql_error());
while($xcat = mysql_fetch_array($resultcat)) 
{
$listcat .= "<option value=\"$xcat[category_id]\">$xcat[category]</option>";
}

In the add_product page i then used this code to show the drop down box

<td>Product Category :</td>
            <td><select name="category">
                <option value=0></option>
<? 
echo "$listcat"; ?>
</select>

But what do i use now for the edit page?

Thx in advance

[rheroux]

Well, if category_id is indeed unique and is being auto incremented, you can use that in another page or another part of the same page to formulate a query that will pull all the information based on that category id.

Something like this:

<?php
if($_POST['addchanges'])
{
$sql = "UPDATE category SET category_name = '".$_POST['categoryname']."' WHERE category_id = '".$_POST['id']."'";
mysql_query($sql) or die ("Could not execute query");
}

if($_POST['editcategory'])
{
$sql = "SELECT * FROM category WHERE category_id = '".$_POST['category']."'";
$result = mysql_query($sql) or die ("Could not execute query.");
if(mysql_num_rows($result) == 0)
{
echo "Sorry, we could not find that category.";
}
while($row = mysql_fetch_array($result))
{
$id = $row['category_id'];
$category_name = $row['category_name'];
}
?>
<form action="<?=$PHP_SELF?>" method="post">
<input type="text" name="categoryname" value="<?=$category_name?>"><br>
<input type="hidden" name="id" value="<?=$id?>"><br>
<input type="submit" name="addchanges" value="Submit Changes">
</form>
<?php
}
?>

<form action="<?=$PHP_SELF?>" method="post">
<td>Product Category :</td>
            <td><select name="category">
                <option value=0></option>
<?php 
echo "$listcat"; ?>
</select>
<input type="submit" name="editcategory" value="Edit this category">
</form>

Of course, you'd need to change the queries to match what the field names actually are in your table.

[Bluelove]

but i want to edit the catagorie together with the rest of the product information, like name, stock, price etc...

[Bluelove]

maybe it's better when i post the complete code i already have?
so you can see where i need the code to display the slected ones?