Add or change a value of JSON key with jquery or javascript

Question

I have a JSON string(?) that I have returned from $.ajax() and named it data. Some of the values are empty and I need to

Answer 1

It seems if your key is saved in a variable. data.key = value won't work.

You should use data[key] = value

Example:

data = {key1:'v1', key2:'v2'};

var mykey = 'key1'; 
data.mykey = 'newv1';
data[mykey] = 'newV2';

console.log(data);

Result:

{
  "key1": "newV2",
  "key2": "v2",
  "mykey": "newv1"
}