ways to make forms more convenient

[sneakyimp]

i have a site that lets people post and search events.

i've noticed that when a user spends a long time on a form either posting an event or choosing their search parameters that it's very easy to lose this information.

problem 1: accidentally click the forward or back buttons on your browser the form gets reset when you return to the page
i don't see that there is much that can be done - unless somehow the form is being evaluated by php every time you visit. Might there be some way to just cache the form...like send a Pragma or Cache-Control header that tells the browser and/or server to only re-evalute the php code under certain conditions? What might some conditions be?

Problem 2: if you take a good amount of time filling ou the elaborate search form and submit it you get the results, but when you click 'back' the form is reset rather than reflecting your latest search.
I am considering putting the user's search parameters in session when they click submit. if they click back after viewing the search results, the search page always looks in the session to see if there are any values there so you will see the last parameters you selected rather than a blank form.

this gets tricky though. for a couple of reasons:
my site uses GET for its forms so that users can email search results to each other (like google). i don't want a search that someone emails or IMs to you to automatically replace the search in your session
if the user opts to work with the search emailed or IMed from a friend, i do want it to take over the session - but only if they explicitly click a link or button

so i'm thinking of setting up my search form like this:

*** SEARCH FORM ***

if POST data {

  if POST is valid store params in SESSION and redirect to results with params
     in the query string (e.g., results.php?start_date=1/1/2001&foo=bar) 

  if POST is not valid, show the form using the POST data

} else if no POST data {

  if SESSION has search params, show the form with those

  else if GET has search params show the form with those

  else - no params, show blank form

}

then my results page will
perform the search, always looking to the GET vars for the search params.
if there are not GET params, then ERROR
* show a link to adopt the current GET params as my SESSION search

Does that sound viable?

[etully]

While I hate Javascript and love PHP, I think that Javascript is the better solution for this problem because, as you said, pressing the back button can often wipe the form.

Here's what I would do:

1. Put an onchange event on every single text field, radio button, checkbox and textarea on the page that calls a JS function called store_data
2. Write the store_data function so that it automatically loops though every element in the form, reads the name and value of the element and writes it to a cookie and then write one extra cookie called "form_saved" and set the value to "1".
3. Put an onload event in the body of the page that checks to see if form_saved has a value and then loop through all the elements in the form and populate them with the cookie value.

The nice thing about such a function is that it's not specific to any one form so that all you would have to do is include the .js file once in the page. You could even program it to set the onchange event on every element so that you wouldn't have to manually put the event on each form element.

And you could go even one step further... you could use GreaseMonkey to insert that script into other people's web sites so that your nifty functionality would improve every web site you ever visit.

I know that this isn't the answer that you were expecting... but it's the most elegant solution I can think of... even though I hate JS!! I have code snippets that I've written that do each of the things that I've mentioned in this post but I've never put them all together for this particular purpose.

Instead of writing them to individual cookies, you could write them all to one cookie (with some delimiter) so that you don't overwhelm the user's cookie cache with too many cookies.

[sneakyimp]

that sounds like it would work, but i can imagine it would be quite difficult to cover all the various kinds of form inputs and get it working on any given browser that may show up.

this site (phpbuilders.com) seems to be more user-friendly for forms than mine.

for instance, enter some text in the 'Quick Reply' area at the end of this post.
click 'back'
then click 'forward'

the text is still there!

on my site, the text i typed will have disappeared.

why is it different?

[etully]

why is it different?

I've been wondering that for years. I'd love to know the answer.