fig16_11.pl

PERL语言资料 可以用于PERL程序设计

#!/usr/bin/perl
# Fig. 16.11: fig16_11.pl
# Add or remove a book from cart and print cart contents

use warnings;
use strict;
use CGI qw( :standard );

my @cart = readCookie();
my $remove = param( "remove" );
my @book;

if ( $remove ) {
   my $number = param( "number" );

   # The book is removed from the cart array
   @book = splice( @cart, 4 * ( $number - 1 ), 4 );

   # The new array is written to the cookie
   writeCookie( @cart );
   print( header() );
   print( start_html( "Book removed" ) );

   print <<"   End_Remove";
   <center><p>The book <i>$book[0]</i> has been removed.</p>
   <a href = "fig16_11.pl">Return to cart</a>
   <br>
   <a href = "fig16_13.pl">Sign Out</a>
   End_Remove

}
else {
   @book = param( "newbook" );
   
   # Add the book the user wants to the cart array
   push( @cart, @book );

   # If there is nothing in the cart, 
   # simply show the items for sale
   if ( !@cart ) {
      print( redirect( "fig16_12.pl" ) );
      exit;
   }

   # Change cookie so it has the new entry
   writeCookie( @cart );
   print( header() );
   print( start_html( "Shopping Cart" ) );

   print <<"   End_Add";
   <center><p>Here is your current order.</p>
   <table border = "1" cellpadding = "7">
      <tr>
         <th>Item</th>
         <th>Name</th>
         <th>Year</th>
         <th>ISBN</th>
         <th>Price</th>
         <th></th>
      </tr>
   End_Add

   my $counter = 1;
   my $total = 0;
   my @cartCopy = @cart;

   # print out the cart for the user
   while ( @book = splice( @cartCopy, 0, 4 ) ) {
      print( "<tr><form method = \"post\"" );
      print( "action = \"fig16_11.pl\">" );
      print( "<td>$counter</td>" );
      print( "<td>$book[ 0 ]</td>" );
      print( "<td>$book[ 1 ]</td>" );
      print( "<td>$book[ 2 ]</td>" );
      print( "<td>$book[ 3 ]</td>" );
      print( "<td>", submit( "Remove" ), "</td>" );

      param( "remove", 1 );    # set "remove" variable to true
      param( "number", $counter );   # book number to remove
      print( hidden( "remove" ) );
      print( hidden( "number" ) );
      print( "</form></tr>" );

      $book[ 3 ] =~ s/\$//;          # remove $ sign
      $total += $book[ 3 ];          # add price
      $counter++;
   }

   print( "<tr><th colspan = \"4\">Total Order</th><th>" );
   printf( "\$%0.2f", $total );      # print the total

   print( "</tr>" );
   print( "</table><br>" );
   print( "<a href = \"fig16_12.pl\">Buy more books</a>" );
   print( br() );
   print( "<a href = \"fig16_13.pl\">Sign out</a>" );
}
print( end_html() );

sub writeCookie
{
   my $expires = "Monday, 11-JUN-01 16:00:00 GMT";
   print( "Set-Cookie: " );
   print( "CART=", join( "\t", @_ ), "; expires=$expires\n" );
   return;
}

# Read the user's cookies
# Return the information from the CART cookie
sub readCookie
{
   my @cookieValues = split( "; ", $ENV{ 'HTTP_COOKIE' } );
   my $name;
   my $value;
   my @data;

   foreach ( @cookieValues ) {
      ( $name, $value ) = split ( "=" );

      if ( $name eq "CART" ) {
         @data = split ( "\t", $value );
         last;
      }
   }
   return @data;
}

###########################################################################
#  (C) Copyright 2001 by Deitel & Associates, Inc. and Prentice Hall.     #
#  All Rights Reserved.                                                   #
#                                                                         #
#  DISCLAIMER: The authors and publisher of this book have used their     #
#  best efforts in preparing the book. These efforts include the          #
#  development, research, and testing of the theories and programs        #
#  to determine their effectiveness. The authors and publisher make       #
#  no warranty of any kind, expressed or implied, with regard to these    #
#  programs or to the documentation contained in these books. The authors #
#  and publisher shall not be liable in any event for incidental or       #
#  consequential damages in connection with, or arising out of, the       #
#  furnishing, performance, or use of these programs.                     #
###########################################################################