Submitting a form simply using POST and MAILTO? How bad an idea is it?

We have a customer who looks after a bunch of his ow开发者_JAVA百科n small websites and wants to submit his forms using POST and mailto and wants our advice. He says it's been working fine for years but stopped working when he changed his hosting.

I haven't even thought about submitting forms this way since about page 12 of Teach Yourself HTML more than a decade ago. In order to provide him with advice, I did a quick test submitting a form with mailto and seems to me it all happens client side anyway and the main flaw therefore is that it's wholly unpredictable. Sometimes it'll sort of work, I guess.

First question is, how can it be affected by a change of hosting? Surely my customer is mistaken?

Follow up question: how to advise him? Remember the guy is very keen on this way of doing things, so if we're to wean him off it it has to be done gently.

Note: the fact so that the resulting email contains the form data in a hard-to-read form does not worry him at all so that is not a concern.

First question is, how can it be affected by a change of hosting? Surely my customer is mistaken?

It can't, it is pure client side.

My best guess is that the new hosting, includes email hosting, and that includes a spam filter which is catching the form submissions. (The format the data comes out in is pretty mangled IIRC).

Follow up question: how to advise him? Remember the guy is very keen on this way of doing things, so if we're to wean him off it it has to be done gently.

Tell him that mailto: as a form action requires the user to be running certain combinations of software, and that sufficient users don't use those combinations that it has a massive failure rate.

For example, anybody who uses a webmail service and not a local email application will be unable to use the form. Worse case scenario is that they end up suffering a blizzard of dialog boxes requesting their email account settings that they have no idea what to do with.

See the mailto myth for further reading on the subject.

First question :- Can;t see why change of hosting stops this from working, I bet it stop working for another reason and he blamed this!

Second question: :- Find instances where this does not work. E.g.

1. Does it work on all browsers across all platforms?
2. What happens if a mail client is not installed on the client?

etc.

My advice is if you can find enough instances where this does not work then he may change his mind.