Question

I have an array of nodes.
Each node has an array of children and a pointer to its parent.
I would like to serialize it using JSON.stringify, but with the parent pointers I obviously end up with circular references, and JSON throws an exception. What can I do to work-around the circular references and serialize with JSON?

Related question: Chrome sendrequest error: TypeError: Converting circular structure to JSON

Answer 1

You should create a customized toJson function in the objects that have parents.

From the documentation

If an object being stringified has a property named toJSON whose value
is a function, then the toJSON method customizes JSON stringification
behavior

var x = {
  foo: 'foo',
  toJSON: function () {
    return 'bar';
  }
};
var json = JSON.stringify({x: x});

So you could create that function in the objects that have parent references, something like this maybe?

MyObj = function(){
    this.xxx = 'foobar';
    this.zzz = 'foooobar';
    this.name = 'foo';
    this.parent = ...;
    toJSON = function(){
        tmp = '{'
        for(prop in MyObj){
            if(prop == 'parent'){
                tmp += 'parent: "'+ this['parent'].name +'"'; //maybe?? optional!
            }else{
                tmp += prop + ':' + this[prop].stringify + ','; //you will still use the browser function
            }
            tmp += '}            
        }
        return tmp;
    }
}