It does not work as I expected. it changes all member items prop.
just as this post descripts.
http://stackoverflow.com/questions/19640823/dynamically-set-readonly-attribute-of-properties-in-a-propertygrid
just as this post descripts.
http://stackoverflow.com/questions/19640823/dynamically-set-readonly-attribute-of-properties-in-a-propertygrid