Date type is not allowed in JSON. If we need to have a date, we have to include it as a string and then we can convert it back to date object later

var text = '{"name":"John", "birth":"1986-12-14", "city":"New York"}';

var obj = JSON.parse(text);
obj.birth = new Date(obj.birth);

document.write(obj.name + ", " + obj.birth)

Also we can use the second parameter of the

JSON.parse()

function, called

reviver

that checks each property, before returning the value

var text = '{ "name":"John", "birth":"1986-12-14", "city":"New York"}';

var obj = JSON.parse(text, function (key, value) {
  if (key == "birth") {
    return new Date(value);
  } else {
    return value;
  }
});

document.write(obj.name + ", " + obj.birth)