Perl 101: The email form - More Regular Expressions (
Page 4 of 5 )
As I mentioned
earlier, the regular expression we created on the previous page was pretty basic
(you may well be wondering what a complex regexe looks like, but try not to for
now). Now that we've covered the basics, it's time to improve on our regex.
unless ($name =~ /^[\w ]/)
{
print "Oops
you entered your name incorrectly - please go back and check it<br>";
die;
} This works fine for filtering the users name, but
what about his email address? Email addresses contain periods and at symbols, so
we'll need to allow for those. In the previous section we talked about how
characters inside the square brackets are alternates. To allow @ and . we simply
add them to what we already have:
unless ($email =~
/^[\w @.]/)
{
print "Oops you entered your email incorrectly - please go
back and check it<br>";
die;
} And for the actual
message we'll again limit it to letters, number, underscores and spaces:
unless ($message =~ /^[\w ]/)
{
print
"Sorry, you can only use letters, numbers, underscores and spaces in your
message<br>";
die;
} Putting It All Together
So finally we have a complete script, which now looks like this:
#!/usr/bin/perl
use CGI;
$q = new CGI;
$sendmailpath = "/usr/lib/sendmail";
$myemail =
"pete\@p-smith.co.uk";
$name = $q->param("name");
$email =
$q->param("email");
$message = $q->param("message");
print
"Content-type:text/html\n\n";
unless ($name =~ /^[\w ]/)
{
print
"Oops you entered your name incorrectly - please go back and check
it<br>";
die;
}
unless ($email =~ /^[\w @.]/)
{
print "Oops you entered your email incorrectly - please go back and check
it<br>";
die;
}
unless ($name =~ /^[\w ]/)
{
print
"Oops you entered your message incorrectly - please go back and check
it<br>";
die;
}
open(MAIL, "| $sendmailpath -t");
print MAIL "To: $myemail";
print MAIL "Reply: $email";
print
MAIL "Subject:Webmail $name";
print MAIL "\n";
print MAIL "$message";
close MAIL;
print "<html><body>Thank you for your
comments, you mail has been sent"; Upload it as you did earlier
then go back to your hHTML form, fill it in, and submit it. If all goes well you
will receive the 'Thank You' message. If not, it's time to check through your
script for typos again. Wait a few minutes then check your email. You should
have received the message you sent from the form.
