Question Description

Need help with my Computer Science question – I’m studying for my class.

 Exercise 5-2
In this project, you will create a Web page that allows visitors to your
site to sign a guest book that is saved to a text ?le. Ensure that the
Projects directory has read and write permissions for everyone.
1.   Create a new document in your text editor and type the
         declaration,  element, document head, and
         element. Use the strict DTD and “Guest Book” as the
        content of the  element.
                   2.   Add the following text and elements to the document body:
                        Enter your name to sign our guest book
                        
                        First Name 
                        Last Name 
Show Guest Book
                        

                   3.   Save the document as GuestBook.html in the Projects direc-
                        tory for Chapter 5.

                   4.   Create a new document in your text editor and type the
                         declaration,  element, document head, and
                         element. Use the strict DTD and “Sign Guest Book” as
                        the content of the  element.

                   5.   Add the following script section to the document body:
                        

                   6.   Add the following if statement to the script section to check
                        whether the user ?lled in the ?rst name and last name ?elds:
                        if (empty($_POST['?rst_name']) || empty($_
                        POST['last_name']))
                             echo "You must enter your ?rst and last
                                  name. Click your browser's Back button to
                                  return to the Guest Book.n";

                   7.   Add the following else clause to the end of the script section.
                        The statements in the else clause use the fwrite() function
                        to add visitor names to a text ?le named guestbook.txt.
                        else {
                             $FirstName = addslashes($_POST['?rst_name']);
                             $LastName = addslashes($_POST['last_name']);
                             $GuestBook = fopen("guestbook.txt", "ab");
                             if (is_writeable("guestbook.txt")) {
                                  if (fwrite($GuestBook, $LastName . ", " .
                                            $FirstName . "n"))
                                       echo "Thank you for signing our
                                            guest book!n";
                                  else
                                       echo "Cannot add your name to the
                                            guest book.n";
                             }

 else
                   echo "Cannot write to the ?le.n";
              fclose($GuestBook);
        }

   8.   Save the document as SignGuestBook.php in the Projects
        directory for Chapter 5.
                                                                        291
   9.   Create a document named ShowGuestBook.php that dis-
        plays the names of visitors who have signed the guest book.
        Use the read?le() function to display the contents of the
        guestbook.txt ?le. Note that you will need to use the 
        element for Web browsers to recognize the line breaks.

  10. Open GuestBook.html in your Web browser by enter-
      ing the following URL: http:///PHP_Projects/
      Chapter.05/Projects/GuestBook.html. Test the form to see if
      you can write data to and read data from the guestbook.txt
      ?le.

  11. Close your Web browser window.