Question

我是JS的新手。我必须编写一个包含（循环，条件语句和运算符）的函数...

提出3个问题 - 就我而言
两次尝试正确回答
保持一致的正确答案
显示总计到屏幕

我只有如下所示。我现在完全被困住了。求救！

function capitalCity()

{

    var answer1 = prompt("What is the capital of France?","");
    var answer2 = prompt("what is the capital of Scotland?","");
    var answer3 = prompt("what is the capital of Spain?","");



    if ( answer1 == "Paris" && answer2 == "Edinburgh" && answer3 == "Madrid")
    {
    alert("You have passed!");
    }

    else if ( answer1 != "Paris" || answer2 != "Edinburgh" || answer3 != "Madrid")
    {
    alert("Have another go!");
    capitalCity();
    }
}

Answer 1

以下是您问题的另一种解决方案。您可以根据需要使用任意数量的问题：

function askQuestions(secondTime) {
    var questionsAndAnswers = [
        ["What is the capital of France?",   "Paris"], 
        ["what is the capital of Scotland?", "Edinburgh"], 
        ["what is the capital of Spain?",    "Madrid"]
    ];
    var correctAnswers = 0;

    for(var i = 0; i < questionsAndAnswers.length; i++) {
        var questionAndAnswer = questionsAndAnswers[i],
            answer = prompt(questionAndAnswer[0], "");

        if(answer.toLowerCase() === questionAndAnswer[1].toLowerCase()) {
            correctAnswers++;
        }
    }

    var ratio = Math.round(correctAnswers/questionsAndAnswers.length*100);
    alert(ratio + "% questions are correct");

    if(!secondTime && ratio < 100) {
        askQuestions(true);
    }
}

askQuestions();

Answer 2

如果您希望仅运行两次，请在循环外部创建一个计数器变量。这就是它的样子。

var count = 0;

function capitalCity()
{
    if(count >= 2){
    count = 0;
    alert('you failed...');
    return;
    }
    var answer1 = prompt("What is the capital of France?","");
    var answer2 = prompt("what is the capital of Scotland?","");
    var answer3 = prompt("what is the capital of Spain?","");



    if ( answer1 == "Paris" && answer2 == "Edinburgh" && answer3 == "Madrid")
    {
    alert("You have passed!");
    count = 0;
    }

    else if ( answer1 != "Paris" || answer2 != "Edinburgh" || answer3 != "Madrid")
    {
    alert("Have another go!");
    count++;
    capitalCity();
    }
}

Answer 3

更新：我错过了两次尝试的标准。

以下是更新的解决方案[demo]：

function capitalCity() {
    var countryCapitals = {
        France: 'Paris',
        Scotland: 'Edinburgh',
        Spain: 'Madrid'
    };

    var correctAnswersCount = 0;

    for (var country in countryCapitals) {
        var question = 'What is the capital of ' + country + '?',
            answer = countryCapitals[country];

        if (prompt(question) == answer || prompt('Try again:\n' + question) == answer) {
            correctAnswersCount++;
        }
    }

    alert('Number of correct answers: ' + correctAnswersCount);
}

capitalCity();

请注意，使用提示/提醒会产生相当糟糕的用户界面，但是当您在问题中使用提示时，它会使答案变得简单。

Answer 4

function Trivia(attempts, attempt) {
    var questions = [],
        correct = 0;
        attempt = attempt || 0;
    questions.push({
        question: 'What is the capital of France?',
        answer : 'Paris',
    });
    questions.push({
        question: 'What is the capital of Scotland?',
        answer : 'Edinburgh',
    });
    questions.push({
        question: 'What is the capital of Spain?',
        answer : 'Madrid',
    });
    for (var i in questions) {
        var answer = prompt(questions[i].question);
        if (answer.toLowerCase() == questions[i].answer.toLowerCase()) {
            correct++;
        }
    }
    if (correct < questions.length) {
        if (attempt >= attempts - 1) {
            alert('Sorry, u suck too much');
            return;
        }
        alert('U suck, retry');
        Trivia(attempts, attempt+1);
    } else {
        alert('Good Job!');
    }
}
Trivia(3);
//call trivia with 3 max tries

比较运营商

4 个答案: