using textual input to modify script and HTML code

[tsheff]

Here's my question:
I have a dynamic script file that does purchase orders and invoices. The user selects the company for shipping/receiving via menus, which then puts all needed info (address etc) in text fields. What we want is, if it is a new vendor or customer, we can just type it in the text field, click a 'new vendor' check box and have it store the info (with the rest of the vendors inside the HTML code itself) and also add the entry to the menu.

I guess specifically the question is about the file writing capabilities of javascript. Can I somehow just insert the new vendor info into the code text?


Thanks for any clues.