如何检查某个项目是否出现在数组中，并重新选择新的项目？

Question

好吧，所以我认为我是这样做的，但事实上出了问题，因为我的代码永远运行。请记住，我上高中并且对编码很陌生，因此可能有一个非常简单的解决方案，但我无法解决这个问题。

我有一个数据文件，其中有各种问题数据。我的目标是从数据中随机选择一个问题，然后根据id数组检查问题的ID。如果该ID出现在该数组中，我想重新运行随机选择功能来选择另一个问题。我想继续这样做，直到我有一个没有出现的问题。

var dataFile = { 
'01': { questionID: '00100A', text: 'Random question number one?'}, 
'02': { questionID: '00200B', text: 'Random question number two?'}, 
'03': { questionID: '00300C', text: 'Random question number three?'}, 
'04': { questionID: '00400D', text: 'Random question number four?'}, 
'05': { questionID: '00500E', text: 'Random question number five?'}, 
'06': { questionID: '00600F', text: 'Random question number six?'}, 
'07': { questionID: '00700G', text: 'Random question number seven?'}, 
'08': { questionID: '00800H', text: 'Random question number eight?'}, 
'09': { questionID: '00900I', text: 'Random question number nine?'}, 
'10': { questionID: '01000J', text: 'Random question number ten?'}}; 

var questionsAsked = ['00100A', '00300C', '00500E', '00700G', '00900I']; 

const keys = Object.keys(dataFile).map(key => dataFile[key]); 

let selectedQuestion = keys[Math.floor(Math.random() * keys.length)]; 

let questionID = (selectedQuestion.questionID) 

if (questionsAsked.includes(questionID)) { 
    let selectedQuestion = keys[Math.floor(Math.random() * keys.length)]; 
    return selectedQuestion; 
} else { 
    questionsAsked.push(questionID); 
    return selectedQuestion; 
} 

数据文件中有9个数据。还有一些已经被问到的问题。我首先映射dataFile以获取问题数据，然后从中选择一个随机问题。我从该问题中提取questionID，然后使用if ... else语句来检查问题ID是否出现在questionsAsked数组中。如果是这样，我重新选择另一个问题。如果没有，则将id推入数组中，并返回问题。

我的问题是，如果if语句为true，则会选择另一个问题，但不会再次检查它是否出现在questionsAsked数组中。也尝试了一段时间循环，看看是否有什么区别，但那是当我的代码卡在一个无限循环。

while (questionsAsked.includes(guID)) { 
    let selectedQuestion = keys[Math.floor(Math.random() * keys.length)]; 
    let questionID = (selectedQuestion.questionID); 
} 

questionsAsked.push(guID); 
return selectedQuestion; 

任何建议将非常大大appriciated

Answer 1

看看这个解决方案：

var dataFile = { 
 
'01': { questionID: '00100A', text: 'Random question number one?'}, 
 
'02': { questionID: '00200B', text: 'Random question number two?'}, 
 
'03': { questionID: '00300C', text: 'Random question number three?'}, 
 
'04': { questionID: '00400D', text: 'Random question number four?'}, 
 
'05': { questionID: '00500E', text: 'Random question number five?'}, 
 
'06': { questionID: '00600F', text: 'Random question number six?'}, 
 
'07': { questionID: '00700G', text: 'Random question number seven?'}, 
 
'08': { questionID: '00800H', text: 'Random question number eight?'}, 
 
'09': { questionID: '00900I', text: 'Random question number nine?'}, 
 
'10': { questionID: '01000J', text: 'Random question number ten?'}}; 
 

 
var questionsAsked = ['00100A', '00300C', '00500E', '00700G', '00900I']; 
 

 
const keys = Object.keys(dataFile).map(key => dataFile[key]); 
 

 
//wrapped it in a function 
 
function randomQuestion() 
 
{ 
 
    let selectedQuestion = keys[Math.floor(Math.random() * keys.length)]; 
 

 
    let questionID = (selectedQuestion.questionID) 
 

 
    //if the question does not exists in the array indexOf will return -1 
 
    //so push the answer into the array and return selected 
 
    if (questionsAsked.indexOf(questionID) === -1) { 
 
    questionsAsked.push(questionID); 
 
    return selectedQuestion; 
 
    } else { 
 
    //if it does exist make it recursive and run again until it does. 
 
    if (questionsAsked.length < keys.length) 
 
    { 
 
     return randomQuestion(); 
 
    } 
 
    else { 
 
    return {"message" : "There are no more random questions."}; 
 
    } 
 
    } 
 
} 
 

 
document.querySelector("button").addEventListener("click", function(){ 
 
    console.log(randomQuestion(), questionsAsked); 
 
});

<button>role it</button>