asked on

Scalar matching and if/elsif statement problems...

Here's my script. I want the script to be able to take the "email" input value and check and see if it already exists in a file, if not, add it, if it does, alert the user that it already exists.

Code:
--------------------------------------------->>
#!/usr/bin/perl -wT

use CGI qw(:standard);
use CGI::Carp qw(warningsToBrowser fatalsToBrowser);

use Fcntl qw(:flock :seek);

print "Content-type: text/html\n\n";

sub add {
open(USER, ">>users.txt") or &dienice("Sorry\, there has been a problem\nadding you to our User File\.\nClick Back on Your Browser and try again\.: $!");
flock(USER, LOCK_EX);
seek(USER,0,2);
print USER param('email');
print USER "\n";
close(USER);

print <<EndHTML;
<html>
<head>
<script>
function goBack(){
history.go(-1);
}
</script>
</head>
<body onload="goBack();">
</body>
</html>
EndHTML
}

open(USER, "users.txt") or &dienice("Sorry\, there has been a problem\nadding you to our User File\.\nClick Back on Your Browser and try again\.: $!");
flock(USER, LOCK_SH);
seek(USER,0,0);
@list = <USER>;
close(USER);

$email = param('email');
$email =~ s/%(..)/pack("c",hex($1))/ge;

$num = $#list;
for ($i = 0, $i => $num, $i++){
$comp = $list[$i];

if ($comp == $email){
print "Sorry, there has been an error, the e-mail address you entered already exists. Please Click Back on Your Browser and try again.<br>";
last;
}
elsif ($i => $num){
add();
last;
}
}
---------------------------------------------<<

Can anyone tell me why the following statement always comes up true, despite the user's e-mail not being in the file?
--------------------------------------------->>
if ($comp == $email){
print "Sorry, there has been an error, the e-mail address you entered already exists. Please Click Back on Your Browser and try again.<br>";

last;
}
---------------------------------------------<<

And if I change it to the "eq" string comparison it always returns false, even when the e-mail address is in the file.

It was also suggested to me to use "List::Compare" with the "get_union" function, only to find that my Hosting company doesn't have the "List::Compare.pm" module installed.

Any ideas?

ASKER CERTIFIED SOLUTION

kandura

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ziffgone

ASKER

Would the "unless($found)" statement come outside "close USER;" then? As the add(); function will write to the file when "$email" is not found.

ziffgone

ASKER

Never mind, tested it myself.

BING, BING, BING, BING....

kandura gets the points!

I wanted to use the "while" function anyway, so your solution is a perfect fit.

Thanks a b'zillion kandura!

Regards...