MYSQL and Listboxes

Anon

I need to be able to populate 2 listboxes with data from my database. I have it setup to where i have a table named category and a table named subcategory. i have figured out how to load the data into the category listbox but what I want to be able to do is when I select my category in the listbox I want the subcategories to show in the other listbox that correspond to my category is there any way to do this please help.

nostradamus

Have you tried to put the listboxes in diffrent frames and to load the second frame "on change" of the listbox in the first one? You have to use java for this, but it is no problem to get a skript somewhere (for instance at "selfhtml") and put it into your code.

Anon

Ok I have it working somewhat I am using php_self to submit the form after i use an onchange on the category listbox. The Category that was selected is being placed in a variable. I then run a query sort of like this Select * FROM Category WHERE CatID=$Category. After that the 2nd listbox is updated with the correct sub-categories. My new problem however when I do a php_self the data that I selected from the first listbox has changed back to the default value that it was before I changed it. Do you know a way that I can use php_self and still keep the data that I originally selected?

Anon

This is a common problem with web pages.

You can save the selected value for your first list box in a session variable. When you return to that page, check this value and set your SELECTED attribute accordingly.

If that's about as clear as mud, I can dig out some old code for you somewheres.

Anon

The best way of doing this is loading the table data into a client side array.

With the onchange event handler, you can then dynamically alter the data in the <select> tag.

If you do reload the page, you will need to add a querystring as a marker for your first list box.

Anon

I understand the concept I have used querystring in asp. I am new to php though Can you give me an example code of how to load the data into a client side array and set the querystring?

Thank you