Difference between toJSON() and JSON.Stringify()

Question

if you need to read or clone all of a model’s data attributes, use its toJSON() method. This method returns a copy of the attributes as an object (not a J

Answer 1

• JSON.stringify() - Any valid JSON representation value can be stringified.

  The JSON.stringify(..) utility will automatically omit undefined, function, and symbol values when it comes across them. If such a value is found in an array, that value is replaced by null (so that the array position information isn't altered). If found as a property of an object, that property will simply be excluded.

  JSON stringification has the special behavior that if an object value has a toJSON() method defined, this method will be called first to get a value to use for serialization.

• toJSON() - to a valid JSON value suitable for stringification.

  One example, JSON.stringify() an object with circular reference in it, an error will be thrown. toJSON() can fix it as following.

  var o = { };
  var a = {
      b: 32,
      c: o
  };
  
  // circular reference
  o.d = a;
  
  // JSON.stringify( a ); // an error caused by circular reference
  
  // define toJSON method
  a.toJSON = function() {
       return { b: this.b };
  };
  
  JSON.stringify( a ); // "{"b":32}"