can someone PLEASE help me with drops downs, auto-populating from database

[jbrill]

I posted a few days ago about this same topic but never got any real answers so im going to post absolutely everything i have in order to get some answers. I am trying to use a "category" drop down (populated from category table in database), once an item is selected, i would like it to populate the sub-category drop down ( populated from subcategory table in database).

 

Im really stuck here and need some help.

here is my database table info for the two drop downs.

 

table : category

Structure: cat (basic id field) and category ( actual name of the category)

 

table : subcategory

Structure: cat ( corresponds with the above "cat" id field) , subc (the main subcategory table id) and subcat ( the real name of the subcategory)

 

 

any help would be greatly appreciated! i really need to get this done!

thanks so much in advance! 

 

 

[Yesideez]

At the top of the script I presume you're reading the form using $_POST so let's say we're reading the drop-down box called "category"

<?php
  $cat=$_POST['category'];
?>

 

Next, we want to read the categories table and make the drop-down box selections:

<?php
  $htmcats='';
  $query=mysql_query("SELECT * FROM `categories` ORDER BY `category` ASC");
  while ($fetch=mysql_fetch_assoc($query)) {
    $htmcats.='<option value="'.$fetch['categoryid'].'"'.($cat==$fetch['categoryid'] ? ' selected="selected"' : '').'>'.$fetch['category'].'</option>';
  }
?>

 

That reads through the categories table and builds a string called $htmcats with the options. If the option selected by the user matches one of the categoryid's from the table then it is made selected. Handy if your form validates the data from the user so they don't have to keep selecting the category each time they mess up the form. Next we want to add that list of options onto the code:

Category: <select name="category"><?=$htmcats?></select>

 

That's all there is to it. Just adapt the code for the subcategories.

[Yesideez]

btw, the above PHP is presuming that your table `categories` has the following fields:

categoryid: primary index, integer

category: varchar - category name

[Yesideez]

If you want to make it so that the second drop-down box is populated to a separate list of sub categories depending on what the first category was chosen, you'll need Javascript for that.

 

I try and stay clear of Javascript - it bears the mark of the devil

[jbrill]

They way i want this to work will probably need to include javascript because i dont want anything to appear in the subcategory drop down until somethign is selected from the category drop down.

[Yesideez]

Javascript it is then.

 

Funny - I only just PM'd you!

[Yesideez]

You might be better off posting this question in the Javascript forum.

[jbrill]

somebody here must know javascript!

 

[Yesideez]

Yeah but its the wrong forum.

 

Its like talking about cars in a birdwatching forum - you wouldn't get many replies!