Javascript/jQuery - 如何在提交表单之前暂停循环的执行？

Question

我正在遵循本指南:http://javascriptissexy.com/how-to-learn-javascript-properly/ 目前，我正在尝试在该页面下方进一步详细介绍动态测验。思路:循环遍历所有问题，对数组中的每一个问题，新建一个表单，等待提交，处理提交的信息，继续下一个循环交互。我目前遇到了麻烦，因为我不知道如何暂停循环以等待提交表单。我该怎么做呢？请参阅下面的代码，以及具体的函数“presentQuestion()”。

$(document).ready(function () {

var questionArray = [
{ question: "The Netherlands", choices: ["Amsterdam", "Monaco", "Chisinau"], correctAnswer: 0 },
{ question: "Austria", choices: ["Bern", "Vienna", "Copenhagen"], correctAnswer: 1 },
{ question: "Bulgaria", choices: ["Budapest", "Sofia", "Minsk"], correctAnswer: 1 },
{ question: "Sweden", choices: ["Stockholm", "Malmo", "Gothenburg"], correctAnswer: 0 },
{ question: "Latvia", choices: ["Vilnius", "Skopje", "Riga"], correctAnswer: 2 },
{ question: "Lithuania", choices: ["Riga", "Skopje", "Vilnius"], correctAnswer: 2 }];;

var score;
var questionField = $("#questionDiv");
var tallyField = $("#tallyDiv");

$("#startButton").on("click", function () {
    resetTally();
    askQuestions();
});

$("#answerButton").on("click", function () {
    // The button from the generated question form.
    // When pressed, call evaluateAnswer() 
})

function askQuestions() {
    for (var i = 0; i < questionArray.length; i++) {
        questionField.empty();
        presentQuestion(questionArray[i]);
    }
}

function presentQuestion(q) {
    questionField.append("What is the capital of " + q.question + "?");
    questionField.append('<form method="POST">');

    for (var i = 0; i < q.choices.length; i++) {
        questionField.append(q.choices[i] + ' <input type="radio" name="answers" id="' + i + '"/></p>')
    }

    questionField.append('<input type="submit" id="answerButton" value="submit answer"/>');

    // to do: code that pauses the askQuestions() for loop
}

function evaluateAnswer() {
    // to do: take the submitted form info and evaluate the given answer. If correct, send  
    // feedback to updateTally()
}

function updateTally(givenAnswer) {
    if (givenAnswer == true) {
        // to do: increase score by 1, loop iteration ends and the next iteration 
        // in askQuestions() starts
    }
    else {
        // Same, but with a score increase of 0
    }
}

function resetTally() {
    tallyField.text("Start answering!");
    score = 0;
}

});

Answer 1

简短的回答是:

不要使用循环。使用 javascript 变量来跟踪用户当前所在的测验步骤。

长答案:

1) 创建一个新变量来跟踪测验步骤

$(document).ready(function () {

var quizstep = 0;

var questionArray = [
{ question: "The Netherlands", choices: ["Amsterdam", "Monaco", "Chisinau"], correctAnswer: 0 },
{ question: "Austria", choices: ["Bern", "Vienna", "Copenhagen"], correctAnswer: 1 },
{ question: "Bulgaria", choices: ["Budapest", "Sofia", "Minsk"], correctAnswer: 1 },
{ question: "Sweden", choices: ["Stockholm", "Malmo", "Gothenburg"], correctAnswer: 0 },
{ question: "Latvia", choices: ["Vilnius", "Skopje", "Riga"], correctAnswer: 2 },
{ question: "Lithuania", choices: ["Riga", "Skopje", "Vilnius"], correctAnswer: 2 }];

...

2) 将 askQuestions 函数替换为下面的函数。

...
function askQuestions() {

    if(quizstep < questionArray.length)
    {
        questionField.empty();
        presentQuestion(questionArray[quizstep]);
        quizstep++;
    }
}
...