simple variable pass to another page gives me error

rossvri

i am just trying to learn to pass a simple variable from a checkbox to the next page. answer should just be true or false i think. when i do this, i get the following error.

CGI Error
The specified CGI application misbehaved by not returning a complete set of HTTP headers. The headers it did return are:

here is the html and the script. what am i doing wrong?

<HTML>

</FORM>

</BODY>

</HTML>

and the script is:

<HTML>

<?php
php_track_vars;

if ($subscribe) {
echo "you are subscribed";
echo $_GET[$subscribe];
}
else
{echo "you are not subscribed";
}

</BODY>

</HTML>

thanks,

ross

bernouli

echo $_POST['subscribe'];

echo $HTTP_POST_VARS[$subscribe];

since you are using POST method sending the form

btw, what does php_track_vars mean?

rossvri

i found it in the book 'php essentials'

it says 'enabling variable tracking, or placing variables in global arrays, is an option configured when the PHP engine is installed on the server. if you are unsure whether variable tracking is turned on, you can add the line <?php_track_vars?> to the beginning of your script.

i did this in frustration...🙁

oops, i can't believe what i did wrong...sticky fingers. a typo. my action = "subscripe" instead of "subscribe"

it's always the stupid stuff that will kill you...

the if/else works as expected now but for some reason, if the $subscribe fails in the if portion and the the code drops down into the then portion, i get the following error even though i get the correct "you are not subscribed". what gives?

Warning: Undefined variable: subscribe in c:\inetpub\wwwroot/subscribe.php on line 11

the new code is below so that the line numbers make sense

<HTML>

if ($subscribe) {

echo "you are subscribed";

} else {

echo "you are not subscribed";

}

</BODY>

</HTML>

ross:o

MrAlaska

Get track_vars out of there unless you are doing something through the track_vars array, otherwise you are burning resources storing unused variables.

Your original script, at least at a glance, looks like it should work except for one thing. You are posting using method 'POST' but you are trying to access $subscribe through the $_GET array.

I think you will find checkboxes a bit easier to work with if you assign values to them, but this is essentially your script modified a little to make it work and self posting to make it all on one page:

<?php
if (isset($_POST['button'])){
	?>
	<HTML>
	<HEAD>
	<TITLE> </TITLE>
	</HEAD>
	<BODY BGCOLOR="#C0C0C0">
	<?php
	extract($_POST);
	if (isset($subscribe)) {
		echo "you are subscribed";
	}
	else {
		echo "you are not subscribed";
	}
	?>
	</BODY>
	</HTML>
	<?php
} else {
	?>
	<HTML>
	<HEAD>
	<TITLE> </TITLE>
	</HEAD>
	<BODY BGCOLOR="#C0C0C0">
	<FORM METHOD = "POST">
	<P><INPUT TYPE="checkbox" NAME="subscribe"></P>
	<P><input type = "submit" name = "button" Value = "subscribe"></P>
	</FORM>
	</BODY>
	</HTML>
<?php } ?>

rossvri

thanks MrAlaska, that works MUCH better. you are right, the first script seemed to work but not quite right as i posted. i had named my php file subscripe instead of subscribe...🙁

saidbakr

all php books, telle us that php has a wonderfull way to deal with variables from HTMLforms, it's to make the name of the form element is the variable name. That's good, but this property works with some php versions and other are not I think the solution in PHP.INI file but HOw I DON"T know?