新的Javascript和编程。我的代码出错了？

Question

嗨，我是JavaScript和编程的新手。我一直在用科德罗米来帮助我学习。然而，我最近遇到了一个问题，我已经创建了一组代码，我在Codecademy中，我似乎找不到问题所在。下面是代码：

var mInQuestion = prompt('Do you play a musical instrument?').toLowerCase;
if (mInQuestion == yes) {
var musInstrument = prompt('Which instrument do you play?').toLowerCase;
switch (musInstrument) {
    case 'piano':
        console.log('Oh great! Piano is wonderful!');
        break;
    case 'guitar':
        console.log('Wow I love guitar as well!');
        experience = prompt('Did you play when you were little?').toLowerCase;
        interest = prompt('And do you like playing it?')toLowerCase;
        if (experience && interest == yes||y) {
            console.log("That's great! You must be a guitar master!");
        }
        else {
            console.log("Keep learning! It will be great. Or you could do piano?");
        }
        break;
    case 'flute':
        console.log('Oh that\'s cool! You know I used to play flute as well!');
        break;
    default:
        console.log('Oh I\'m not sure I\'ve heard of that instrument...sorry');
        break;
}
else if (mInQuestion == no) {
console.log('Oh you don\'t? You should pick one like the piano or the guitar!');
}
else {
console.log('Your answer doesn\'t make sense...');
}

Answer 1

你的吉他有点问题。您需要声明这两个变量的经验和兴趣，再加上您缺少了一个。在toLowerCase之前。您还在if语句的末尾缺少一个结束括号}。如果要测试字符串，则还需要用引号对if语句进行格式化，并且每个条件都需要完全写出。

 var mInQuestion = prompt('Do you play a musical instrument?').toLowerCase;
if (mInQuestion == yes) {
    var musInstrument = prompt('Which instrument do you play?').toLowerCase;
    switch (musInstrument) {
        case 'piano':
            console.log('Oh great! Piano is wonderful!');
            break;
        case 'guitar':
            console.log('Wow I love guitar as well!');
            var experience = prompt('Did you play when you were little?').toLowerCase; //need to declare these
            var interest = prompt('And do you like playing it?').toLowerCase;
            if ((experience ==='yes' ||experience==='y') && (interest === 'yes'|| interest ==='y')) {
                console.log("That's great! You must be a guitar master!");
            }
            else {
                console.log("Keep learning! It will be great. Or you could do piano?");
            }
            break;
        case 'flute':
            console.log('Oh that\'s cool! You know I used to play flute as well!');
            break;
        default:
            console.log('Oh I\'m not sure I\'ve heard of that instrument...sorry');
            break;
    }} //need bracket here
else if (mInQuestion == no) {
    console.log('Oh you don\'t? You should pick one like the piano or the guitar!');
}
else {
    console.log('Your answer doesn\'t make sense...');
}

Answer 2

看看这里的这一行：

if (mInQuestion == yes) {

您正在尝试检查mInQuestion是否是字符串"yes"，但实际上正在检查它是否等于不存在的变量yes。把引号放在yes和no周围。

还请注意这一行：

if (experience && interest == yes||y) {

您不能检查这样的多个条件，您必须清楚地对每个检查：

if ((experience == 'yes' || experience == 'y') && (interest == 'yes' || interest == 'y'))

而且，无论您在任何地方调用toLowerCase都是不正确的。您正在尝试调用一个函数，但是省略了括号。这意味着您的变量实际上是函数，而不是您想要的字符串。每次调用toLowerCase后插入括号

Answer 3

语法错误错过了。在这里，兴趣=提示符(‘您喜欢它吗？’)toLowerCase；

 break;
case 'guitar':
    console.log('Wow I love guitar as well!');
    experience = prompt('Did you play when you were little?').toLowerCase;
    interest = prompt('And do you like playing it?').toLowerCase;
    if (experience && interest == yes||y) {
        console.log("That's great! You must be a guitar master!");
    }