参考资料：
- http://einverne.github.io/post/2016/01/boost-learning-note-7.html
- http://www.ruanyifeng.com/blog/2009/05/data_types_and_json.html
- http://www.freeformatter.com/javascript-escape.html#ad-output
- http://jsoneditoronline.org/
- http://xzhoumin.blog.163.com/blog/static/408811362013642305423/
