如何在 Javascript json 变量中添加新键及其值

Question

Suppose that I have a variable user and I need to append a new question as a key and its value to that newly created id

users variable

const  users= {
      johndoe: {
        answers:{
            "6ni6ok3ym7mf1p33lnez": "optionTwo",
            "vthrdm985a262al8qx3do": "optionTwo",
            "xj352vofupe1dqz9emx13r": "optionOne"
        }
       
      },
     joseph: {
        answers:{
            "6ni6ok3ym7mf1p33lnez": "optionTwo",
            
        }
       
      }
      
} 

New key and its value and the user who answered the question

const questionId = "thisisnewkey";
const newQuestionAnswer = "optionTwo";
const userWhoAnsweredTheQuestion = "joseph";

Before appending a question and its answer its mandatory to find the user who answered that question Expected output

const  users= {
      johndoe: {
        answers:{
            "6ni6ok3ym7mf1p33lnez": "optionTwo",
            "vthrdm985a262al8qx3do": "optionTwo",
            "xj352vofupe1dqz9emx13r": "optionOne"
        }

      },
     joseph: {
        answers:{
            "6ni6ok3ym7mf1p33lnez": "optionTwo",
             "thisisnewkey":"optionTwo"


        }

      }

} 

Answer 1

You can use bracket notation ( [] ) for dynamic property of the object:

users[userWhoAnsweredTheQuestion].answers[questionId] = newQuestionAnswer;

 const users= { johndoe: { answers:{ "6ni6ok3ym7mf1p33lnez": "optionTwo", "vthrdm985a262al8qx3do": "optionTwo", "xj352vofupe1dqz9emx13r": "optionOne" } }, joseph: { answers:{ "6ni6ok3ym7mf1p33lnez": "optionTwo", } } } const questionId = "thisisnewkey"; const newQuestionAnswer = "optionTwo"; const userWhoAnsweredTheQuestion = "joseph"; users[userWhoAnsweredTheQuestion].answers[questionId] = newQuestionAnswer; console.log(users);

Answer 2

Suppose that I have a variable user and I need to append a new question as a key and its value to that newly created id

users variable

const  users= {
      johndoe: {
        answers:{
            "6ni6ok3ym7mf1p33lnez": "optionTwo",
            "vthrdm985a262al8qx3do": "optionTwo",
            "xj352vofupe1dqz9emx13r": "optionOne"
        }
       
      },
     joseph: {
        answers:{
            "6ni6ok3ym7mf1p33lnez": "optionTwo",
            
        }
       
      }
      
} 

New key and its value and the user who answered the question

const questionId = "thisisnewkey";
const newQuestionAnswer = "optionTwo";
const userWhoAnsweredTheQuestion = "joseph";

Before appending a question and its answer its mandatory to find the user who answered that question Expected output

const  users= {
      johndoe: {
        answers:{
            "6ni6ok3ym7mf1p33lnez": "optionTwo",
            "vthrdm985a262al8qx3do": "optionTwo",
            "xj352vofupe1dqz9emx13r": "optionOne"
        }

      },
     joseph: {
        answers:{
            "6ni6ok3ym7mf1p33lnez": "optionTwo",
             "thisisnewkey":"optionTwo"


        }

      }

} 

Answer 3

By using ES6 code should be

 ...users,
       [userWhoAnsweredTheQuestion]:{
          ...users[userWhoAnsweredTheQuestion],
              answers: {
              ...users[userWhoAnsweredTheQuestion].answers,
                [questionId]: answer
                    }
                }