Problem on passing the variable to PHP script

Hellomonkey

I wrote a testing page as below :

<html>
<form method=post action="">
Please enter your login name <br>
<input type=text name="username"> <br><br>
<input type=submit value="Submit">
</form><br><br>

Your entered :

<?php
echo ($username);
?>

</html>

When I entered the login name and click the submit button, it show only the "Your entered : " without the login name. I am running this on my Redhat8.0 machine with Apache 2.0 and php 4.2.2 (bundled) installed with the default settings.

Would anyone tell me what's the problem.

Many thx.

raymie

for security reasons the register_globals setting is now by default off.

Your variable should be referred to as

$_POST['username']

Hellomonkey

Thanks for your help. Do you mean it should be

echo ($_POSTusername);

raymie

No.

I meant what I said in the first place 🙂

The $POST is an array as is $GET and $_SESSION amongst others. They are similar to normal arrays except that they are global in scope.

Hellomonkey

Thx again but it still doesn't work. I found that when I added action='testing.php' in the form tag, the variable $_POST['username'] can be seen in testing.php.

nexgen_x

In the form tag, type:
action="<?=PHP_SELF?>"

This tells the script to reload itself with the new variables.

You can then call each one just by putting a $ in front of the name of the field (so the value submitted for username will be stored in the variable $username).

raymie

The reply from nexgen_x is not correct.

The PHP version is one which with the default settings (AS CONFIRMED) has register_globals set to off. This means that the POST and GET variables amongst others are NOT resolved automatically.

nexgen_x

Hmm, I guess the server I'm on have different settings, then, as they work fine for me.

raymie

That's exactly it, it is a major cause of 'problems' at the moment since it was a recent change is default value.

If you have a page with the command phpinfo() on it then you will see your default values, in your case (and in mine) the register_globals setting will be on which means that of the variables in the global arrays such as $_POST are registered automatically (as are session variables etc).

In the case of the original question however the person states that the values for PHP 4.2 are all as per the defaults and this is certainly a version where the default is off and hence his/her problem.

if you do not control your own server settings then you may have to watch for this in the future since I suspect that a lot of hosts will eventually switch to the default settings.

The setting can, if allowed, be altered via .htaccess files but it is best practice (in my opinion) to get used to it being off now before it is forced off.

nexgen_x

ahh thanks for clearing that up.
Regarding that, can you just type

global $username

at the top of the script to call the variable from a previous page?

Also, does this effect variables in the URL, eg:
/script.php?username=bob&id=224&password=g7suFk ?

<-- decided to take your advice and get used to global variables being off...

raymie

No, when register_globals is off there is no such variable as username.

There is only a variable called $POST['username'] or perhaps $GET['username'] depending on how the variable is passed.

The reason for this is security, it stops someone setting up variables via the URL and having these being passed in to the script and perhaps circumventing security since you may think that they were, for example, session variables.

Have a look at http://www.zend.com/zend/art/art-sweat4.php

Hellomonkey

After I renamed the file from .html to .php, it works. (although I still don't know the reason and I just copied the example from a book. May be I should read more before I start).

I am terribly sorry to let you waste times in helping me. I have to say many many thanks to those who gave me the advices.

raymie

If you really want it you can force .html files to be treated as php (or any other suffic you want).

I assume that it was using the $_POST array which worked once you changed the suffix to PHP, if however it was $username then you do not have the default settings for 4.2.2 as you thought since it was 4.2.0 and above which have the register_globals setting turned off by default.