passing vars from email to form

I want to make my mailshots a bit more clever for my customers. Basically, I send a mailshot once or twice a month to all names in my database. The customer then RSVP's by clicking the "Yes" or "No" links.
When they click these links, they are presented with a form on my web page.
As all the customers details are in my database, how can I set the process up to automatically fill in as many of the boxes as possible when they click the link? (Such as email address, postal address etc...) I'm fine with querying the DB, I just need to know how to pass the vars to the form from the email.

Are you looking for something like this:

// get vars from database
$name = ...(whatever you use to get data from a database)
etc...

<form>
<input type=text name=name value="<?php print $name ?>">
</form>

What I am looking for is storing data in a hidden field or as part of the link within the email message received by customers.
My web page displays a form, on the the fields is named email. When the user clicks the link within the email, the field $email is passed thru to my form and inputted into the email field. I could then use the value to query the database and get the rest of the users details.
I have tried using http://mysite.com/yes?email=someone@somewhere.com but it doesn't work.

If you use this in php version 4.1 or later you shoul be able to use

$_GET['email']

to do your db query

else use

$HTTP_GET_VARS['email']

you could also embed the db unique id for the user (same concept as using the email)in the url sent to the user, then the form page would use that var "id" to query the db, get the info to prefill the form.

I tried this...

The link within the email simply reads <a href="http://mysite.com?uid=261">Click here</a>
but the field remains blank. What am I doing wrong?

can you call $_GET within a function? maybe you need to declare it as global first.

$_GET is a superglobal...no need to declare it global.

Are you sure you are using php version 4.1.0 or higher? If not, use $HTTP_GET_VARS['uid'] and you will need to place global $HTTP_GET_VARS; at the top of your script....

Try echoing out both $HTTP_GET_VARS['uid'] and $_GET['uid'] in your function and seeing if they have values...

Also, $PHP_SELF probably isn't going work inside the function. You will need to place a global $PHP_SELF; at the top of the function to make it work....

are you sure $row contains data

try

print_r($row)

Thanks guys, worked a treat using