循环阵列 object

Question

I am trying to loop through this array

var questions = [
    {
        ask: 'is Javascript the best language?',
        correct: 0,
        answer : [
            {text: 'yes'},
            {text: 'No'}
        ]
    },
    {
        ask: 'is Javascript the most popular language?',
        correct: 1,
        answer : [
            {text: 'yes'},
            {text: 'No'}
        ]
    },

]

and the point is I want to get every question with this loop and get these questions in console log

var currentQuestion = questions.length;

for( var i = 0; i < currentQuestion; i++){
   console.log(questions[i]);
}

but console.log says: Uncaught TypeError: Cannot read property 'length' of undefined

Answer 1

It looks like the variable questions is not included in the same file.

Answer 2

more information at https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_Objects about the js objects.

 var questions = [ { ask: 'is Javascript the best language?', correct: 0, answer: [ {text: 'yes'}, {text: 'No'} ] }, { ask: 'is Javascript the most popular language?', correct: 1, answer: [ {text: 'yes'}, {text: 'No'} ] }, ]; var currentQuestion = questions.length; for( var i = 0; i < currentQuestion; i++){ console.log(questions[i].ask); } // es6 way questions.map(q => { // console.log(q.ask); // will get all the questions })

Answer 3

Use for of.. :

 var questions = [ { ask: 'is Javascript the best language?', correct: 0, answer: [ {text: 'yes'}, {text: 'No'} ] }, { ask: 'is Javascript the most popular language?', correct: 1, answer: [ {text: 'yes'}, {text: 'No'} ] }, ] for(let values of questions){ console.log(values); }