C#拓展方法，自动映射类

    public static class Mapper
    {
        /// <summary>
        ///  类型映射,默认字段名字一一对应
        /// </summary>
        /// <typeparam name="TDestination">转化之后的model，可以理解为viewmodel</typeparam>
        /// <typeparam name="TSource">要被转化的实体，Entity</typeparam>
        /// <param name="source">可以使用这个扩展方法的类型，任何引用类型</param>
        /// <returns>转化之后的实体</returns>
        public static TDestination MapTo<TSource,TDestination>(this TSource source)
            where TDestination : class
        {
            if (source == null) return default(TDestination);
            var config = new MapperConfiguration(cfg => cfg.CreateMap<TSource, TDestination>());
            var mapper = config.CreateMapper();
            return mapper.Map<TDestination>(source);
        }

        /// <summary>
        /// 集合列表类型映射,默认字段名字一一对应
        /// </summary>
        /// <typeparam name="TDestination">转化之后的model，可以理解为viewmodel</typeparam>
        /// <typeparam name="TSource">要被转化的实体，Entity</typeparam>
        /// <param name="source">可以使用这个扩展方法的类型，任何引用类型</param>
        /// <returns>转化之后的实体列表</returns>
        public static IEnumerable<TDestination> MapToList<TSource, TDestination>(this IEnumerable<TSource> source)
            where TDestination : class
            where TSource : class
        {
            if (source == null) return new List<TDestination>();
            var config = new MapperConfiguration(cfg => cfg.CreateMap<TSource, TDestination>());
            var mapper = config.CreateMapper();
            return mapper.Map<List<TDestination>>(source);
        }
    }