I'm looking to have a table that can be added to by just typing into the last row and clicking on the "Add" button at the end of the row. All other rows in the table can be deleted by clicking on a button in their rightmost column.
My problem is that forms can't wrap only one row and validate as XHTML. If I make the form wrap the entire table, it'll include the rows which have a form as their last cell too. And forms within forms are definitely not valid.
Suggestions?
Thanks for clarifying the situation. The way I see it you have a few options here:
Are you using (can you use) JavaScript? If so, you can easily modify the submission URI based on which button was pressed. You can thus get rid of all forms except for table-wrapping one.
Alternatively, depending on your requirements, you may be able to replace your "delete" buttons with links (possibly styled like buttons) in which case you won't need forms to wrap them. Note that this approach does not require javascript UNLESS you need to handle a situation when someone begins to fill last row and then clicks on "delete" on some other row and you want to preserve incomplete changes made to last row inputs. In this case you'd still need to use javascript to submit the form so #1 above would probably be better.
Bite the bullet and submit to the same URI. Distinguish what button was pressed by button name. You can always redirect to appropriate URI at that point.
Make your peace with non-validating html :-)