Printcode: c2f.pl



#! /usr/bin/perl -T

# Celsius to fahrenheit (and back again).

use CGI qw[:standard];
use strict;

$| = 1;

my $celsius = param( "celsius" );
my $fahrenheit = param( "fahrenheit" );

# if either is non-numeric, render as "0".
for ($celsius, $fahrenheit) {
    s/^[^-0-9].*/0/
}

# check for (ne "") rather than a straight boolean True to ensure we still
#  convert zero values.
if ($celsius ne "") {
    $fahrenheit = sprintf( "%4.2f", ($celsius * (9 / 5)) + 32 );
} elsif ($fahrenheit ne "") {
    $celsius = sprintf( "%4.2f", ($fahrenheit - 32) * (5 / 9) );
}

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

print "<HTML>\n" .
      "    <HEAD>\n" .
      "        <TITLE>Celcius-to-Fahrenheit Temperature Converter</TITLE>\n" .
      "        <LINK REL=\"shortcut icon\" HREF=\"/favicon.ico\" TYPE=\"image/x-icon\" />\n" .
      "    </HEAD><BODY><FONT FACE=\"Arial,Helvetica\">\n" .
      "        <H1>Celcius-to-Fahrenheit Temperature Converter</H1>\n" .
      "        <HR ALIGN=\"left\" WIDTH=\"90%\">\n ".
      "        <FORM ACTION=\"/cgi-bin/c2f.pl\" METHOD=\"post\">\n" .
      "            <TABLE BORDER=\"0\" WIDTH=\"60%\">\n" .
      "                <TR>\n" .
      "                    <TD>Celsius:</TD>\n" .
      "                    <TD ALIGN=\"right\"><INPUT TYPE=\"text\" WIDTH=\"10\" MAXLENGTH=\"10\" NAME=\"celsius\" VALUE=\"$celsius\"></TD>\n" .
      "                </TR><TR>\n" .
      "                    <TD>&nbsp;</TD>\n" .
      "                    <TD ALIGN=\"right\"><INPUT TYPE=\"submit\" VALUE=\"Convert to Fahrenheit\"></TR>\n" .
      "                </TR>\n" .
      "            </TABLE>\n" .
      "        </FORM>\n".
      "        <HR ALIGN=\"left\" WIDTH=\"90%\">\n ".
      "        <FORM ACTION=\"/cgi-bin/c2f.pl\" METHOD=\"post\">\n" .
      "            <TABLE BORDER=\"0\" WIDTH=\"60%\">\n" .
      "                <TR>\n" .
      "                    <TD>Fahrenheit:</TD>\n" .
      "                    <TD ALIGN=\"right\"><INPUT TYPE=\"text\" WIDTH=\"10\" MAXLENGTH=\"10\" NAME=\"fahrenheit\" VALUE=\"$fahrenheit\"></TD>\n" .
      "                </TR><TR>\n" .
      "                    <TD>&nbsp;</TD>\n" .
      "                    <TD ALIGN=\"right\"><INPUT TYPE=\"submit\" VALUE=\"Convert to Celsius\"></TR>\n" .
      "                </TR>\n" .
      "            </TABLE>\n" .
      "        </FORM>\n".
      "        <HR ALIGN=\"left\" WIDTH=\"90%\">\n ".
      "        Return <A HREF=\"http://trichotomy.ca/index.php\">Home</A>.<BR>\n" .
      "        View Perl <A HREF=\"http://trichotomy.ca/cgi-bin/printcode.pl?filename=c2f.pl\">Source Code</A>.<BR>\n" .
      "        <FONT SIZE=\"-1\">C2F code copyright 2001 Sean C. Nichols</FONT>\n" .
      "    </FONT></BODY>\n" .
      "</HTML>\n";