如何将Expression <func <dto，bool >>转换为Expression <func <entity，bool >>

Question

我想转换可以通过LINQ转换为SQL的真实表达式 从DTO表达式到实体表达式。 试图构建表达式，使用DTO实体映射器调用表达式，但表达式（逻辑上）未转换为SQL

// Function that contains the converter



public List<EngagementTypeModel> Filter(Expression<Func<EngagementTypeModel, bool>> filter) {
            var body = filter.Body;
            var Parameter = filter.Parameters[0];
            // Model is the DTO

            // NOT this ..
            // Expression<Func<EngagementTypeEntity,bool>> ConvertedExpression = (EngagementTypeEntity e) => filter.Compile()(BindEntityToModel(e));

            // Something like this
            var ConvertedExpression1 = Expression.Lambda<Func<EngagementTypeEntity, bool>>(filter, Expression.Parameter(typeof(EngagementTypeEntity), Parameter.Name));
            return _context.EngagementTypeEntities.Where(ConvertedExpression1).Select(x=>BindEntityToModel(x)).ToList();
        }


// API
[HttpPost]
        public ActionResult<string> SomeBusinessFilter()
        {
            _engagementTypeService.Filter(x => x.EngagementType == "foo" && x.Time < DateTime.Now && x.EngagementModel.EngaementTypeID == Guid.Empty);
            return Json(Ok("Hey"));
        }
``