Change date format for Json

var value = dto.CreatedDate;
if (value.substring(0, 6) == "/Date(") {
var dt = new Date(parseInt(value.substring(6, value.length - 2)));
var dtString = dt.getFullYear();
}

Change date format /Date(1337878800000+0700)/ to regular date format, example dd/mm/yyyy hh:mm:ss ?????? (JSON)