Listing 1: The version of edit-quizfile that displays the form

#!/usr/bin/perl -w


use strict;
use diagnostics;
use CGI;        # Available from https://www.perl.com/CPAN
use QuizQuestions;


# Maximum index for questions (starting at 0)
my $MAX_QUESTIONS = 10;


# Create an instance of CGI
my $query = new CGI;


# Print the MIME header that we will always use
print $query->header("text/html");


# Determine how we were invoked
my $request_method = $query->request_method;


# If we were invoked via POST, then ignore things for now
if ($request_method eq "POST")
{
    print $query->start_html(-title => "Not yet implemented");
    print "Sorry, the POST part of this program isn't yet written.</P>\n";
    print $query->end_html;
}
else
{
    # If the query string is empty, then produce a page of HTML
    # containing ISINDEX
    if ($query->param("keywords") eq "")
    {
   print $query->start_html(-title => "Enter a quiz name");
   print "Please enter the name of the quiz you want ";
   print "to create or edit in the below .</P>\n";
   print "<ISINDEX>\n";
   print $query->end_html;
    }
    else
    {
   # Get the name of the quiz
   my $quizname = $query->param("keywords");


   # Create a new instance of QuizQuestions
   my $questions = new QuizQuestions($quizname);


   # Read the questions from disk, ignoring errors
   # (since we will happily create a new quiz)
   $questions->loadFile;


   # Create the header for the HTML page
   print $query->start_html(-title => "Create/Edit a quiz");


   # Define a form
   my $script_name = $query->script_name;
   print "<Form method="POST" action="$script_name">\n";


   # Create the text element for the quiz name
   print "Editing quiz: <input type="text" name="quizname" ";
   print "value="$quizname"></P>\n";
   print "<HR>\n\n";


   # Now create one form element for each existing question

   my $counter = 0;
   foreach $counter (0 .. $MAX_QUESTIONS)
   {
       # Get a particular question
       my ($qtext, $ansA, $ansB, $ansC, $ansD, $correct)
      = $questions->getQuestion($counter);


       # Question text
       print "<H2>Question $counter</H2>\n";
       print "Question text: <input type="text" ";
       print "name="question-$counter" value="$qtext" ";
       print "size="30"></P>\n";


       # Answer A
       print "Answer A: <input type="text" value="$ansA" ";
       print "name="answer-a-$counter" size="30"></P>\n";


       # Answer B
       print "Answer B: <input type="text" value="$ansB" ";
       print "name="answer-b-$counter" size="30"></P>\n";


       # Answer C
       print "Answer C: <input type="text" value="$ansC" ";
       print "name="answer-c-$counter" size="30"></P>\n";


       # Answer D
       print "Answer D: <input type="text" value="$ansD" ";
       print "name="answer-d-$counter" size="30"></P>\n";


       # Correct answer
       print "Correct answer: <select name="correct-$counter">\n";

       my $letter = "";
       foreach $letter ("a","b","c","d")
       {
      print "<option ";
      print "selected " if ($letter eq $correct);
      print "$letter>$letter\n";
       }


       print "</select>\n";
       print "<HR>\n\n";
   }


   # Now that the loop is complete, we can finish things up
   print '<input type="submit" value="Save changes">', "\n";
   print "</HTML>\n";
   print $query->end_html;
    }
}