Express.js req.body parametr array

I have problem with my routes where I want check some data from req.body form

I have route

  app.post(`/${randomQuestionsArray[0].id}`, (req, res) => {
const reqValue = req.body.answer;
console.log(reqValue);
console.log(randomQuestionsArray[0].reqValue);

}),

Fragment of data:

const jsonContent = {
  "questions": [
      {
          "id": "1",
          'slug': "566fghg6",
          "title": "post title 1",
          "desc": "This is a test desc 1",
          "answer1": {
              "answer": "test1",
              "value": true
          },
           "answer2": {
              "answer": "test2",
              "value": false
          },
           "answer3": {
              "answer": "test3",
              "value": false
          },
           "answer4": {
              "answer": "test4",
              "value": false
          }
      },

req.body.answer - give me value of form etc answer1
But I want to take some data from array
I create variable:

const reqValue = req.body.answer; randomQuestionsArray[0].reqValue give me undefined
but if I write by hand: randomQuestionsArray[0].answer1 give me data "answer": "test1", "value": true

How I can put req.body to my array params?

via Marcin Star