// TQuiz class
function TQuiz() {
var obth = this; // stores the object contained in 'this'
var objfiles = {}; // stores the object with "category":"file_name" elements, received in setCateg()
var level = 'level1'; // 'level1' with variant of answers, 'level2' with text field to write the answer
var stopct = 0; // if not 0, countdown-timer not continue, in startCT()
var ctsec = 15; // number of seconds for each quiz
var nquizzes = 0; // total number of quizzes
var nquiz = 0; // stores number of current quiz
var canswer = ''; // for correct answer of current quiz
var nqansw = 0; // number of answered quizzes
var nca = 0; // number of correct answers
var nia = 0; // number of incorrect answers
// TQuiz mode ('qindex' = gets the quiz from next index, 'qrandom' = gets the quiz with index randomly from "iquizzes")
var qmode = 'qindex';
var qctimer = 0; // for countdown-timer (if is 1), shown in #sctimer
var iquizzes = []; // array with indexes of quizzes that must to get randomly
// property /array stores the TQuiz elements ('que'=question, 'ca'=correct answer, 'ia'=array with incorrect answers)
var quizzes = [];
// sets the <select> list with categories, that will be added in #tcateg
// Receives an object with "category":"file_name" elements, and the type of the files ('json')
this.setCateg = function(objf, type) {
objfiles = objf;
var tcateg = ''; var propf = '';
var i = 0; // to can call the method that sets the quizzes, with the first file_name
for(var prop in objfiles) {
if(i === 0) propf = prop;
i = 1;
tcateg += '<option value='+ prop +'>'+ prop +'</option>';
}
// calls thee method to set the TQuiz quizzes of first category
if(type == 'xml') obth.setQuizXML(propf);
else obth.setQuizJSON(propf);
// sets onchange event for <select> with method to call according to type, adds the select list
var onchg = type == 'xml' ? 'onchange="obTQuiz.setQuizXML(this.value)"' : 'onchange="obTQuiz.setQuizJSON(this.value)"';
if(document.getElementById('tcateg')) document.getElementById('tcateg').innerHTML = 'COURSE: <select '+ onchg +'>'+ tcateg +'</select>';
}
// create the XMLHttpRequest object, according browser
var getXmlHttp = function() {
// if browser suports XMLHttpRequest
if (window.XMLHttpRequest) {
// Cretes a instantce of XMLHttpRequest object
xhttp = new XMLHttpRequest();
}
else {
// for IE 5/6
xhttp = new ActiveXObject("Microsoft.XMLHTTP");
}
return xhttp;
}
// this public function gets the XML DOM, parse and adds in quizzes property the TQuiz elements
// receives the property name that has the file to access, in objfiles object
this.setQuizXML = function(propf) {
obth.resetTQuiz();
quizzes = [];
iquizzes = [];
var xhttp = getXmlHttp(); // calls the function for the XMLHttpRequest instance
// make the request to get the file content
xhttp.open("GET", 'TQuiz/'+ objfiles[propf] ,false);
xhttp.send(null);
var xml_dom = xhttp.responseXML; // gets the XML DOM from xml file
var arr_quiz = xml_dom.getElementsByTagName('quiz'); // gets an Array with all "quiz" tags
nquizzes = arr_quiz.length; // number of 'quiz' elements (total quizzes)
// traverses the "arr_quiz" array
for(var i=0; i<nquizzes; i++) {
quizzes[i] = {}; // creates each element in quizzes array, an object that will conteins question elements
// adds in quizzes each 'quiz' element with question (<que>), correct answer(<ca>), and incorrect answers(<ia>)
quizzes[i]['que'] = arr_quiz[i].getElementsByTagName('que')[0].childNodes[0].nodeValue; // question
quizzes[i]['ca'] = arr_quiz[i].getElementsByTagName('ca')[0].childNodes[0].nodeValue; // correct answer
// sets an array with incorrect answers
quizzes[i]['ia'] = [];
var arr_ia = arr_quiz[i].getElementsByTagName('ia');
var nr_ia = arr_ia.length; // number of 'ia' elements
// traverses the array with incorrect answers and adds them in quizzes[][ia]
for(var i2=0; i2<nr_ia; i2++) {
quizzes[i]['ia'][i2] = arr_ia[i2].childNodes[0].nodeValue;
}
}
// adds in #totalq, and #ntotalq the total number of quizzes
if(document.getElementById('totalq')) document.getElementById('totalq').innerHTML = nquizzes;
if(document.getElementById('ntotalq')) document.getElementById('ntotalq').innerHTML = nquizzes;
}
// this public function gets the JSON object and stores it in quizzes property
// receives the property name that has the file to access, in objfiles object
this.setQuizJSON = function(propf) {
obth.resetTQuiz();
quizzes = [];
iquizzes = [];
var xhttp = getXmlHttp(); // calls the function for the XMLHttpRequest instance
// make the request to get the file content
xhttp.open("GET", 'TQuiz/'+ objfiles[propf], true);
xhttp.send(null);
xhttp.onreadystatechange = function() {
if(xhttp.readyState == 4) {
var tobj = xhttp.responseText; // puts in a variable the received data
tobj = tobj.replace(/\\|\r\n|\n|\r/gm, ''); // remove slashes "\" and new lines
eval("quizzes ="+ tobj); // adds the JSON object in quizzes property
nquizzes = quizzes.length; // total number of quizzes
// adds in #totalq, and #ntotalq the total number of quizzes
if(document.getElementById('totalq')) document.getElementById('totalq').innerHTML = nquizzes;
if(document.getElementById('ntotalq')) document.getElementById('ntotalq').innerHTML = nquizzes;
}
}
}
// creates the countdown timer
var startCT = function() {
// if ctsec is > 1
if(ctsec >= 0) {
// if countdown-timer not stoped (stopct is 0)
if(stopct == 0 && document.getElementById('sctimer')) {
document.getElementById('sctimer').innerHTML = ctsec; // shows the countdown timer
setTimeout(startCT, 1000); // Auto-calls the function after 1 second
}
ctsec--; // decreases the value with one unit
}
else obth.getAnswer(0); // to show the correct answer
}
// sets the value for level property, receives the value
this.setLevel = function(lvl) {
level = lvl;
}
// sets the game mode (qindex or qrandom)
var setQmode = function() {
if(document.getElementById('qindex').checked == true) qmode = 'qindex';
else if(document.getElementById('qrandom').checked == true) qmode = 'qrandom';
}
// sets the value of qctimer property, for countdown-timer
this.setQctimer = function(btn) {
if(btn.checked == true) qctimer = 1;
else qctimer = 0;
}
// sets the array with quizzes index, returns a random index (stn is for 'start', or 'next')
var setIQrandom = function(stn) {
// if stn is 'start', sets iquizzes from beginning, else, removes the element with current quiz number from iquizzes
if(stn == 'start') {
for(var i=0; i<nquizzes; i++) iquizzes[i] = i;
}
else {
// gets the index of item with value of number in nquiz, and removes it
var nqr = iquizzes.length; // number of quizzes index in iquizzes
for(var i=0; i<nqr; i++) {
if(iquizzes[i] == nquiz) {
iquizzes.splice(i, 1);
break;
}
}
iquizzes.sort(); // resorts the array
}
return iquizzes[Math.floor(Math.random() * iquizzes.length)];
}
// sets the index number of current quiz (nquiz)
var setNquiz = function(stn) {
// if 'qmode' is 'qrandom' sets with setIQrandom()
// else if stn is 'start' set nquiz with value added in "#nquiz", else, sets the index of next quiz
if(qmode == 'qrandom') nquiz = setIQrandom(stn);
else if(stn == 'start') {
nquiz = document.getElementById('nquiz').value - 1;
// if nquiz<0 or higher then number of quizzes, or not integer number, resets the game, and alerts message
if(nquiz < 0 || nquiz >= nquizzes || !(typeof(nquiz)==="number" && Math.round(nquiz) == nquiz)) {
obth.resetTQuiz();
alert('The value of Starting quiz number must be an integer number between 1 and '+ nquizzes);
}
}
else {
if(nquiz < (nquizzes - 1)) nquiz++;
else obth.resetTQuiz(); // if reached the last quiz
}
}
// starts and shows the quiz, receives the way: 'start' or 'next' to set the index of current quiz
this.sQuiz = function(stn) {
setQmode(); // to set the game mode
setNquiz(stn); // to set the index of current quiz
deBtns(['level1', 'level2', 'qindex', 'nquiz', 'qrandom', 'qctimer', 'squiz'], 'disable'); // to disable buttons (enable Reset)
canswer = quizzes[nquiz]['ca']; // stores correct answer
if(document.getElementById('quiz')) {
// to add countdown-timer if qctimer is different from 0
var addct = (qctimer == 0) ? '' : '<div id="sctimer">0</div>';
// increments the number of answered quizzes, calls answered() to display it
nqansw++;
answered();
// shows the quiz number, quiz question, and element for answer (according to level)
document.getElementById('quiz').innerHTML = addct +'<h4 id="qnr">Quiz No. '+ (nquiz + 1) +'</h4><h4 id="tquestion">○ '+ quizzes[nquiz]['que'] +'</h4><div id="qansw">'+ (level == 'level1' ? qAnswerL1() : qAnswerL2()) +'</div>';
// if qctimer is 1, sets the stopct and ctsec, calls the function for countdown-timer
if(qctimer == 1) {
stopct = 0;
ctsec = 15;
startCT();
}
}
}
// resets the TQuiz game, index-number of quiz, the value in #nquiz field, alerts message
this.resetTQuiz = function() {
nquiz = 0; // index-number of quiz
qctimer = 0; // to disable countdown-timer
// reset answered data
nqansw = 0; nca = 0; nia = 0;
answered();
deBtns(['level1', 'level2', 'qindex', 'nquiz', 'qrandom', 'qctimer', 'squiz'], 'enable'); // to enable buttons (disable Reset)
document.getElementById('nquiz').value = 1;
document.getElementById('qctimer').checked = false;
document.getElementById('quiz').innerHTML = '<center><strong><h2 align = "left"><em><ul><li>Select your course<li>Click on start to begin and on start over to start the quiz again<li>The correct answer will be given if you make a mistake<li>Choose between multiple choice and fill in<li>Select the count down timer to answer each question within 15 seconds</em></h2></strong></center>';
}
// to disable /enable buttons when Start /Reset TQuiz, receives an Array with IDs of buttons, and 'disable' or 'enable'
var deBtns = function(ids, de) {
var nrids = ids.length;
for(var i=0; i<nrids; i++) {
if(de == 'disable') document.getElementById(ids[i]).setAttribute('disabled', 'disabled');
else document.getElementById(ids[i]).removeAttribute('disabled');
}
// removes 'disabled' from Reset (when start), or adds 'disabled' to Reset (when Reset)
if(de == 'disable') document.getElementById('treset').removeAttribute('disabled');
else document.getElementById('treset').setAttribute('disabled', 'disabled');
}
// sets and returns the variant of answers (for Level 1)
var qAnswerL1 = function() {
var qhtml = ''; // quiz question
var nr_ia = quizzes[nquiz]['ia'].length; // number of incorrect answers
// random number used to set randomly the position of correct answer
var randomnr = Math.floor(Math.random() * nr_ia);
// creates the options with answers
for(var i=0; i<nr_ia; i++) {
// if 'i' = randomnr, adds correct answer, and decrease the index, else, incorrect answer
if(i == randomnr) {
qhtml += '<div class="qanswer" onclick="obTQuiz.getAnswer(this)">'+ canswer +'</div>';
randomnr = -1; // to not be again equal to i
i--;
}
else qhtml += '<div class="qanswer" onclick="obTQuiz.getAnswer(this)">'+ quizzes[nquiz]['ia'][i] +'</div>';
}
return qhtml;
}
// returns the text field to write answer (for Level 2)
var qAnswerL2 = function() {
return '<input type="text" id="qanswerl2" /><button onclick="obTQuiz.getAnswer(document.getElementById(\'qanswerl2\'))">Send</button>';
}
// adds data in #answered box, number of answered quizzes, correct and incorrect answers
var answered = function() {
if(document.getElementById('ntotalq')) document.getElementById('ntotalq').innerHTML = nquizzes;
if(document.getElementById('nqansw')) document.getElementById('nqansw').innerHTML = nqansw;
if(document.getElementById('nca')) document.getElementById('nca').innerHTML = nca;
if(document.getElementById('nia')) document.getElementById('nia').innerHTML = nia;
}
// method called when an answer is clicked, receives the object with answer
this.getAnswer = function(answ){
stopct = 1; // to stop countdown-timer
// sets the Correct /Incorrect, answ is 0 when auto-calls from startCT()
if(document.getElementById('qansw')) {
// gets the Answer, delete white-spaces and tags ('qanswerl2' is from text field - Level 2)
if(answ != 0) var qanswer = answ.id == 'qanswerl2' ? answ.value.replace(/^\s+|\<+|\>+|\s+$/g, '') : answ.innerHTML.replace(/^\s+|\s+$/g, '');
// sets Correct or Incorrect answer
if(answ == 0) {
nia++; // incorrect answer
var seeansw = '<h4 id="iansw">Time expired</h4><h4 id="cansw">The Correct answer is:</h4><div id="canswer">'+ canswer +'</div>';
}
else if(qanswer.toLowerCase() == canswer.toLowerCase()) {
nca++; // correct answer
var seeansw = '<div id="canswer">'+ qanswer +'</div><h4 id="cansw">> Correct</h4>';
}
else {
nia++; // incorrect answer
var seeansw = '<strike>'+ qanswer +'</strike><h4 id="iansw">Incorrect, the correct answer is:</h4><div id="canswer">'+ canswer +'</div>';
}
answered(); // to show answered data
// if 'qindex' mode and last quiz, adds message, else, adds Next Button
seeansw += ((qmode == 'qindex' && nquiz == (nquizzes - 1)) || (qmode == 'qrandom' && iquizzes.length == 1)) ? '<h2><em>This the end of the quiz</em></h2>': '<button id="nextq" onclick="obTQuiz.sQuiz(\'next\')">Next</button>';
document.getElementById('qansw').innerHTML = seeansw;
}
}
/* register events */
// onclick on Radio buttons for Level
if(document.getElementById('level1')) document.getElementById('level1').onclick = function(){obth.setLevel('level1');}
if(document.getElementById('level2')) document.getElementById('level2').onclick = function(){obth.setLevel('level2');}
// onclick on Radio buttons for mode, to show /hide the field for starting quiz number
if(document.getElementById('qindex')) document.getElementById('qindex').onclick = function(){document.getElementById('startqn').style.display = 'block';}
if(document.getElementById('qrandom')) document.getElementById('qrandom').onclick = function(){document.getElementById('startqn').style.display = 'none';}
// onclick on Checkbox button for countdown-timer
if(document.getElementById('qctimer')) document.getElementById('qctimer').onclick = function(){obth.setQctimer(this);}
// onclick on Start button
if(document.getElementById('squiz')) document.getElementById('squiz').onclick = function(){obth.sQuiz('start');}
//我有一个来自网站的琐事游戏。我已经能够修改它，但根据问题的数量，用户被问到json文件中的所有问题。但我想限制不。每个测验的问题为10个。
答案 0 :(得分：0)
var arr_quiz = xml_dom.getElementsByTagName('quiz'); // gets an Array with all "quiz" tags
nquizzes = arr_quiz.length; // number of 'quiz' elements (total quizzes)
这是设置问题数量的部分。您可能希望将其替换为以下内容：
var arr_quiz = xml_dom.getElementsByTagName('quiz'); // gets an Array with all "quiz" tags
nquizzes = Math.min(arr_quiz.length,10); // number of 'quiz' elements (total quizzes)
这意味着，您的测验工厂不超过10个问题。如果可用的问题少于10个，则仅使用可用的问题。