javascript - my if statement doesn't work when checking radio input

Question

Im trying to validate radio input to check if its correct answer.
But it skips the line if (answer == allQuestions[q].correctAnswer)

here is whole code https://jsfiddle.net/alcatel/sopfmevh/1/

for (let k = 0; k < answers.length; k++) {
  if (answers[k].checked) {
    answer = answers[k].value;
  }
}

// IT SKIPS THIS LINE !!
if (answer == allQuestions[q].correctAnswer) { // IT SKIPS THIS LINE!!
  alert("correct");
}

q++;
    
populate();

标签： javascriptfor-loopif-statementradio-button

Answer 1

因为我做到了...

const allQuestions = 
        [ { question     : 'Where is Helsinki?'
          , choices      : [ 'Sweden', 'Finland', 'Us' ] 
          , correctAnswer: 1
          } 
        , { question     : 'Where is Stockholm?'
          , choices      : [ 'Norway', 'Iceland', 'Sweden' ] 
          , correctAnswer: 2
          } 
        , { question     : 'Where is Köpenhamn?'
          , choices      : [ 'Denmark', 'Sweden', 'Norway' ] 
          , correctAnswer: 0
          } 
        ] 
function* qList(arr) { for (let q of arr) yield q }

const libQuestion  = document.querySelector('h1')
  ,   formReplies  = document.getElementById('list')
  ,   btNext       = document.querySelector('button')
  ,   DomParser    = new DOMParser()
  ,   qListRead    = qList( allQuestions )
  ,   score        = { correct: 0, count:0 }
  ;
var currentAnswer = ''
  ;
function setNewQuestion()
  {
  formReplies.innerHTML = ''

  let newQuestion = qListRead.next()
  if (!newQuestion.done)
    {
    libQuestion.textContent = newQuestion.value.question
    currentAnswer           = newQuestion.value.correctAnswer
    ++score.count
    newQuestion.value.choices.forEach((choice,indx)=>
      {
      let line = `<label><input type="radio" name="answer" value="${indx}">${ choice}</label>`
        , inLn = (DomParser.parseFromString( line, 'text/html')).body.firstChild
        ;
      formReplies.appendChild(inLn)
      })
    }
  else
    {
    libQuestion.textContent = ` Score = ${score.correct} / ${score.count}`
    btNext.disabled         = true
    }
  }
setNewQuestion()
btNext.onclick=()=>
  {
  if (formReplies.answer.value)
    {
    score.correct += ( currentAnswer == formReplies.answer.value )
    setNewQuestion()
    }
  }

<h1></h1>
<p></p>
<form id="list"></form>
<br>
<button>next</button>