Recursively remove null values from JavaScript object

Question

I have a JSON obj, after some operations (like delete some pieces), I print it and everything looks good except that I have some null values. How do I remove th

Answer 1

Please use this npm package

npm i --save nnjson
var nnjson = require('nnjson');
user = {
  a: null,
  b: 'hello',
  c: {
    c1: 'world',
    c2: null
  }
}
var newUser = nnjson.removeNull(user);
console.log (newUser)

result

{
  b: 'hello',
  c: {
    c1: 'world'
  }
}

Answer 2

Fixing your book array is easy enough - you just have to filter out the nulls. The most straightforward way would probably be building a new array and reassigning it:

var temp = [];
var i;
for (i = 0; i < obj.store.book.length; ++i) {
    if (obj.store.book[i] != null) {
        temp.push(obj.store.book[i]);
    }
}
obj.store.book = temp;

I'm sure there are plenty of other ways, like using jQuery, or the filter function (which I believe is not available in older browsers). You could also loop through the array and splice out the nulls. I just find this way the easiest to read.