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Tolerim
25 days ago

While converting an array to JSON, how can I handle the occurrence of a null value at the top level?

The question has been closed and requires more clarity before accepting any answers. If you want to improve the question, you can add details and clarify the problem by editing the post. Here's the code that you can use to map the submitted answer array to the list. 
this.submittedAnswerlist = this.submittedAnswerArrary.map(function(answer) {
  return answer ? answer.submitted_Ans : null;
});
This will only map the submitted answer object to the list.
Answers(2)
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Vogi
24 days ago
Verified Answer
It seems like you are trying to map the submitted answer array to the list in JavaScript. The code you provided is using the built-in map() method of an array in JavaScript. The map() method creates a new array populated with the results of calling a provided function on every element in the calling array. In your case, you are mapping each submitted answer object to its submitted_Ans property and returning it as a new list. Here's how the code works: 
this.submittedAnswerlist = this.submittedAnswerArrary.map(function(answer) {
  return answer ? answer.submitted_Ans : null;
});
The map() method takes a callback function as an argument that is called for every element in the array. The callback function takes three arguments: - The current element being processed in the array. - The index of the current element being processed in the array. - The array that map() was called upon. In your case, the callback function is: 
function(answer) {
  return answer ? answer.submitted_Ans : null;
}
This function checks if answer is truthy (not null or undefined) and returns its submitted_Ans property if it exists, otherwise it returns null. I hope this helps! Let me know if you have any more questions.

Sources

JavaScript Array.map () Tutorial – How to Iterate Through Elements in ...How to map a javascript array to another javascript arrayjavascript - How to create list of arrays using map? - Stack Overflow
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Tolerim
25 days ago
To map only the object within the array, you can use array destructuring like this: 
this.submittedAnswerlist = [...this.submittedAnswerArrary][1];
This will create a new array with the [1] index object of this.submittedAnswerArrary. The spread operator ... before this.submittedAnswerArrary is used to avoid mutating the original array.
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