我在连接字符串时遇到问题。在我最初在最后一个函数中声明“输出”变量的地方，我能够将正确的问题数量打印到我的模式窗口中。
但是，我从那之后将 2 行的字符串串联起来是行不通的，而且我已经尝试了很多东西。我相信这很简单，但任何帮助将不胜感激！
我不确定有多少代码与解决方案相关，所以我为代码墙道歉。
我是 JS 新手，也是我在 Stackoverflow 上的第一篇文章，因此感谢您提供任何提示或建议。提前致谢！
var randomNum1 = 0;
var randomNum2 = 0;
var correctAnswer = 0;
var questionNumber = 0;
var question = "<h2>Question #: " + questionNumber + "</h2>";
var answersRight = 0;
//jQuery command to make enter key submit answer
$(document).keypress(function(e) {
if (e.which == 13) {
$("#sub").click();
}
});
//questions object
var questionsAsked = [
];
generateRandom();
document.getElementById('finished').style.display = 'none';
//check answer, push question info to array
function check() {
var userAnswer = parseInt(document.getElementById("userAnswer").value);
document.getElementById('userAnswer').value = "";
if (userAnswer === correctAnswer) {
answersRight++
} else {
answersRight += 0;
}
if (questionNumber < 3) {
next();
} else {
document.getElementById('sub').style.display = 'none';
document.getElementById('submitForm').style.display = 'none';
document.getElementById('finished').style.display = 'block';
finish();
}
}
function random() {
return Math.floor(Math.random() * 50) + 1;
}
//generate random numbers
function generateRandom() {
randomNum1 = random();
randomNum2 = random();
document.getElementById("randomNum1").innerHTML = randomNum1;
document.getElementById("randomNum2").innerHTML = randomNum2;
correctAnswer = randomNum1 + randomNum2;
questionNumber += 1;
question = "<h2>Question #: " + questionNumber + "</h2>";
$("#question").html(question);
questionsAsked.push([questionNumber, randomNum1, randomNum2, correctAnswer]);
}
//next button
function next() {
generateRandom();
}
function finish() {
var output = document.getElementById("quizResults").innerHTML = 'You got ' + answersRight + ' out of ' + questionNumber + ' answers correct!';
var percent = Math.round((answersRight / questionNumber) * 100);
output += ' You got ' + percent + '% on this quiz! Outstanding!';
}<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<body>
<div class="container">
<div>
<h1 class="text-center">Welcome to Math World!</h1>
</div>
<div>
<div id="question">
</div>
<div id="questionArea">
<br>
<h3>Add the following numbers</h3>
<h3 id="randomNum1"></h3>
<h3>+</h3>
<h3 id="randomNum2"></h3>
<p id="message"></p>
</div>
<div id="submitForm">
<div class="form-inline">
<div class="form-group">
<label for="answer">Enter Answer:</label>
<input type="text" class="form-control" id="userAnswer" placeholder="Type answer here">
</div>
<button id="sub" type="submit" class="btn btn-primary" onclick="check()">Submit Answer</button>
</div>
</div>
<button id="finished" type="submit" class="btn btn-success" data-toggle="modal" data-target="#myModal">Finish Quiz</button>
</div>
<!-- Modal -->
<div id="myModal" class="modal fade" role="dialog">
<div class="modal-dialog">
<div class="modal-content">
<div class="modal-header">
<button type="button" class="close" data-dismiss="modal">×</button>
<h4 class="modal-title">Quiz Results</h4>
</div>
<div id="quizResults" class="modal-body">
</div>
<div class="modal-footer">
<button type="button" class="btn btn-default" data-dismiss="modal">Close</button>
</div>
</div>
</div>
</div>
<script