Javascript提示计算字符串长度

Question

我正在 Codeacademy 学习 javascript，我正在尝试从提示条目中计算字符串长度并为每个答案显示自定义警报。这是我目前所拥有的：

var answer = prompt('What is your surname?').length;

var responses = {
answer > 5: 'Your name has fewer than five characters',
answer < 5: 'Your name has more than five characters',
defaultResponse: 'You didn\'t answer?'
}

alert(responses[answer] || responses.defaultResponse);

我是否应该在这里某处放置一个 if 语句。还是Switch在这里会更好？

Answer 1

这是一个干净的方法：

var answer = prompt('What is your surname?');
var response;

if(answer.length == 0){
    response = 'You didn\'t answer?';
} else if(answer.length > 5){
    response = 'Your name has fewer than five characters';
} else if (answer.length < 5) {
    response = 'Your name has more than five characters';
}

alert(response);

对于这样的事情，我不会为开关而烦恼。

Answer 2

如果你想使用一个对象来查找答案，你可以这样做

var answer = prompt('What is your surname?').length;

var responses = {
more: 'Your name has more than five characters',
less: 'Your name has fewer than five characters',
default: 'You didn\'t answer?'
}

alert(answer == 0 && responses.default || answer < 5 && responses.less || answer > 5 && responses.more);