Add a javascript confirmation when submitting a quiz attempt

lang/en/quiz.php

@@ -77,6 +77,7 @@ $string['quizclosed'] = "This quiz closed on \$a";
 $string['quizopen'] = "Open the quiz";
 $string['quiznotavailable'] = "The quiz will not be available until: \$a";
 $string['random'] = "Random set";
+$string['readytosend'] = "You are about to send your whole quiz to be graded.  Are you sure you want to continue?";
 $string['regrade'] = "Regrade all attempts";
 $string['regradecomplete'] = "All attempts have been regraded";
 $string['regradecount'] = "\$a->changed out of \$a->attempt grades were changed";

mod/quiz/lib.php

@@ -411,7 +411,9 @@ function quiz_print_quiz_questions($quiz, $results=NULL) {
         return false;
     }
 
-    echo "<FORM METHOD=POST ACTION=attempt.php>";
+    $strconfirmattempt = addslashes(get_string("readytosend", "quiz"));
+
+    echo "<FORM METHOD=POST ACTION=attempt.php onsubmit=\"return confirm('$strconfirmattempt');\">";
     echo "<INPUT TYPE=hidden NAME=q VALUE=\"$quiz->id\">";
 
     foreach ($questions as $key => $questionid) {