continue.php

很棒的在线教学系统

<?php // $Id: continue.php,v 1.39.2.9 2009/03/17 16:24:47 mark-nielsen Exp $
/**
 * Action for processing page answers by users
 *
 * @version $Id: continue.php,v 1.39.2.9 2009/03/17 16:24:47 mark-nielsen Exp $
 * @license http://www.gnu.org/copyleft/gpl.html GNU Public License
 * @package lesson
 **/
    confirm_sesskey();

    require_once($CFG->dirroot.'/mod/lesson/pagelib.php');
    require_once($CFG->libdir.'/blocklib.php');

    // left menu code
    // check to see if the user can see the left menu
    if (!has_capability('mod/lesson:manage', $context)) {
        $lesson->displayleft = lesson_displayleftif($lesson);
    }

    // This is the code updates the lesson time for a timed test
    // get time information for this user
    $timer = new stdClass;
    if (!has_capability('mod/lesson:manage', $context)) {
        if (!$timer = get_records_select('lesson_timer', "lessonid = $lesson->id AND userid = $USER->id", 'starttime')) {
            error('Error: could not find records');
        } else {
            $timer = array_pop($timer); // this will get the latest start time record
        }
        
        if ($lesson->timed) {
            $timeleft = ($timer->starttime + $lesson->maxtime * 60) - time();

            if ($timeleft <= 0) {
                // Out of time
                lesson_set_message(get_string('eolstudentoutoftime', 'lesson'));
                redirect("$CFG->wwwroot/mod/lesson/view.php?id=$cm->id&amp;pageid=".LESSON_EOL."&outoftime=normal");
                die; // Shouldn't be reached, but make sure
            } else if ($timeleft < 60) {
                // One minute warning
                lesson_set_message(get_string("studentoneminwarning", "lesson"));
            }
        }
        
        $timer->lessontime = time();
        if (!update_record("lesson_timer", $timer)) {
            error("Error: could not update lesson_timer table");
        }
    }

    // record answer (if necessary) and show response (if none say if answer is correct or not)
    $pageid = required_param('pageid', PARAM_INT);
    if (!$page = get_record("lesson_pages", "id", $pageid)) {
        error("Continue: Page record not found");
    }
    // set up some defaults
    $answerid        = 0;
    $noanswer        = false;
    $correctanswer   = false;
    $isessayquestion = false;   // use this to turn off review button on essay questions
    $newpageid       = 0;       // stay on the page
    $studentanswer   = '';      // use this to store student's answer(s) in order to display it on feedback page
    switch ($page->qtype) {
         case LESSON_ESSAY :
            $isessayquestion = true;
            if (!$useranswer = $_POST['answer']) {
                $noanswer = true;
                break;
            }
            $useranswer = clean_param($useranswer, PARAM_RAW);
        
            if (!$answers = get_records("lesson_answers", "pageid", $pageid, "id")) {
                error("Continue: No answers found");
            }
            $correctanswer = false;
            foreach ($answers as $answer) {
                $answerid = $answer->id;
                $newpageid = $answer->jumpto;
            }
            /// 6/29/04 //
            $userresponse->sent=0;
            $userresponse->graded = 0;
            $userresponse->score = 0;
            $userresponse->answer = $useranswer;
            $userresponse->response = "";
            $userresponse = addslashes(serialize($userresponse));
            
            $studentanswer = s(stripslashes_safe($useranswer));
            break;
         case LESSON_SHORTANSWER :
            if (isset($_POST['answer'])) {
                $useranswer = $_POST['answer'];
            } else {
                $noanswer = true;
                break;
            }            
            $useranswer = s(stripslashes(clean_param($useranswer, PARAM_RAW)));
            $userresponse = addslashes($useranswer);
            if (!$answers = get_records("lesson_answers", "pageid", $pageid, "id")) {
                error("Continue: No answers found");
            }
            $i=0;
            foreach ($answers as $answer) {
                $i += 1;
                $expectedanswer  = $answer->answer; // for easier handling of $answer->answer
                $ismatch         = false; 
                $markit          = false; 
                $useregexp       = false;

                if ($page->qoption) {
                    $useregexp = true;
                }
                
                if ($useregexp) { //we are using 'normal analysis', which ignores case
                    $ignorecase = '';
                    if ( substr($expectedanswer,strlen($expectedanswer) - 2, 2) == '/i') {
                        $expectedanswer = substr($expectedanswer,0,strlen($expectedanswer) - 2);
                        $ignorecase = 'i';
                    }
                } else {
                    $expectedanswer = str_replace('*', '#####', $expectedanswer);
                    $expectedanswer = preg_quote($expectedanswer, '/');
                    $expectedanswer = str_replace('#####', '.*', $expectedanswer);
                }
                // see if user typed in any of the correct answers
                if ((!$lesson->custom && lesson_iscorrect($pageid, $answer->jumpto)) or ($lesson->custom && $answer->score > 0) ) {
                    if (!$useregexp) { // we are using 'normal analysis', which ignores case
                        if (preg_match('/^'.$expectedanswer.'$/i',$useranswer)) {
                            $ismatch = true;
                        }
                    } else {
                        if (preg_match('/^'.$expectedanswer.'$/'.$ignorecase,$useranswer)) {
                            $ismatch = true;
                        }
                    }
                    if ($ismatch == true) {
                        $correctanswer = true;
                    }
                } else {
                   if (!$useregexp) { //we are using 'normal analysis'
                        // see if user typed in any of the wrong answers; don't worry about case
                        if (preg_match('/^'.$expectedanswer.'$/i',$useranswer)) {
                            $ismatch = true;
                        }
                    } else { // we are using regular expressions analysis
                        $startcode = substr($expectedanswer,0,2);
                        switch ($startcode){
                            //1- check for absence of required string in $useranswer (coded by initial '--')
                            case "--":
                                $expectedanswer = substr($expectedanswer,2);
                                if (!preg_match('/^'.$expectedanswer.'$/'.$ignorecase,$useranswer)) {
                                    $ismatch = true;
                                }
                                break;                                      
                            //2- check for code for marking wrong strings (coded by initial '++')
                            case "++":
                                $expectedanswer=substr($expectedanswer,2);
                                $markit = true;
                                //check for one or several matches
                                if (preg_match_all('/'.$expectedanswer.'/'.$ignorecase,$useranswer, $matches)) {
                                    $ismatch   = true;
                                    $nb        = count($matches[0]);
                                    $original  = array(); 
                                    $marked    = array();
                                    $fontStart = '<span class="incorrect matches">';
                                    $fontEnd   = '</span>';
                                    for ($i = 0; $i < $nb; $i++) {
                                        array_push($original,$matches[0][$i]);
                                        array_push($marked,$fontStart.$matches[0][$i].$fontEnd);
                                    }
                                    $useranswer = str_replace($original, $marked, $useranswer);
                                }
                                break;
                            //3- check for wrong answers belonging neither to -- nor to ++ categories 
                            default:
                                if (preg_match('/^'.$expectedanswer.'$/'.$ignorecase,$useranswer, $matches)) {
                                    $ismatch = true;
                                }
                                break;
                        }
                        $correctanswer = false;
                    }
                }
                if ($ismatch) {
                    $newpageid = $answer->jumpto;
                    if (trim(strip_tags($answer->response))) {
                        $response = $answer->response;
                    }
                    $answerid = $answer->id;
                    break; // quit answer analysis immediately after a match has been found
                }
            }
            $studentanswer = $useranswer;
            break;
        
        case LESSON_TRUEFALSE :
            if (empty($_POST['answerid'])) {
                $noanswer = true;
                break;
            }
            $answerid = required_param('answerid', PARAM_INT); 
            if (!$answer = get_record("lesson_answers", "id", $answerid)) {
                error("Continue: answer record not found");
            } 
            if (lesson_iscorrect($pageid, $answer->jumpto)) {
                $correctanswer = true;
            }
            if ($lesson->custom) {
                if ($answer->score > 0) {
                    $correctanswer = true;
                } else {
                    $correctanswer = false;
                }
            }
            $newpageid = $answer->jumpto;
            $response  = trim($answer->response);
            $studentanswer = $answer->answer;
            break;
        
        case LESSON_MULTICHOICE :
            if ($page->qoption) {
                // MULTIANSWER allowed, user's answer is an array
                if (isset($_POST['answer'])) {
                    $useranswers = $_POST['answer'];
                    foreach ($useranswers as $key => $useranswer) {
                        $useranswers[$key] = clean_param($useranswer, PARAM_INT);
                    }
                } else {
                    $noanswer = true;
                    break;
                }
                // get what the user answered
                $userresponse = implode(",", $useranswers);
                // get the answers in a set order, the id order
                if (!$answers = get_records("lesson_answers", "pageid", $pageid, "id")) {
                    error("Continue: No answers found");
                }
                $ncorrect = 0;
                $nhits = 0;
                $correctresponse = '';
                $wrongresponse = '';
                $correctanswerid = 0;
                $wronganswerid = 0;
                // store student's answers for displaying on feedback page
                foreach ($answers as $answer) {
                    foreach ($useranswers as $key => $answerid) {
                        if ($answerid == $answer->id) {
                            $studentanswer .= '<br />'.$answer->answer;
                        }
                    }
                }
                // this is for custom scores.  If score on answer is positive, it is correct                    
                if ($lesson->custom) {
                    $ncorrect = 0;
                    $nhits = 0;
                    foreach ($answers as $answer) {
                        if ($answer->score > 0) {
                            $ncorrect++;
                    
                            foreach ($useranswers as $key => $answerid) {
                                if ($answerid == $answer->id) {
                                   $nhits++;
                                }
                            }
                            // save the first jumpto page id, may be needed!...
                            if (!isset($correctpageid)) {  
                                // leave in its "raw" state - will converted into a proper page id later
                                $correctpageid = $answer->jumpto;
                            }
                            // save the answer id for scoring