控件中常用的与数据库相关的工具类函数放这个接口中
[ object, uuid(42DF06F4-CBCC-4693-B39D-478CAC243919), dual, nonextensible, helpstring("IMxDrawUtility interface"), pointer_default(unique) ] interface IMxDrawUtility : IDispatch;
MxDrawUtility.idl
接口