input type=button with and without form tag

Question

I have created lots of buttons for a large number of pages (usually 5-10 in a row at the bottom of each page inside a table cell) using input type="button" name="..." value="..." onclick="some javascript event handler" etc, basically to link to other pages of the same group. All these pages are ultimately linked from an iframe tag on a single page. The buttons are working fine offline on my PC at least. But, now I've suddenly realized that I haven't used any 'form' tag for these buttons.

So my question is, is this 'form' tag really necessary? Will there by any problem after I upload? I would prefer not to add the form tag now to so many pages if it's not really necessary, because that's going to be a real drag. But, I don't want to suffer afterwards either.

Answer 1

No it is not necessary as long as you are not doing any Get/Post and grouping form elements together. They should work completely fine without a form tag.

Answer 2

There are two issues to be concerened with:

• Is it valid HTML?

Turns out that it is valid HTML (see Is <input> well formed without a <form>?), so you are on the safe side here.

• Will all common browsers accept it?

After googling around I haven't seen any information on problems wih this use of Input tags. That suggests that all common browsers accept this valid HTML (as they should). When developing any website that is accessible to the general public I would always do a manual cross-browser check to discover any abnormalities certain browsers may habe with my site.

Problem is that you most likely won't be able to tell from looking at your server logs whether certain browsers have a problem with your HTML. It may just not work on IE 6 and you would never be able to find unless a disgruntled customer calls up and informs you.

If this is a generally accessible website get some stats on the most commonly used browsers, decide which ones you want to support, and verify that the website is behaving properly on thiee browsers. This is a pain in the ass, but there is no way I know of to get around that. Browsers may not react to valid HTML properly.

As a rule of thumb, Firefox, Chrome, and Safari unsually behave well, and because of auto-updates most people will have a very recent version installed. If the latest version of the browser works I wouldn't be too concerned that users with some older version will have trouble.

The real test is always Internet Explorer. While version 8 and 9 are pretty standards-compliant, IE 7 certainly needs checking. IE 6 is the worst offender for unusual behavior. It was introduced in 2002, but today still 6% of the population use it! Most of this comes from cracked copies of Windows XP in China, but it is also used quite a lot in corporate networks, where OS and browsers are centrally deployed, and administrators have not managed to progress since early 2000.

In conclusion: Your code is unusual but ok, test it manually on the browsers you expect.