Linq-里面包括 [英] Linq - where inside include

问题描述

我知道这将无法按书面要求进行，但我正努力寻找正确的答案，并且该非功能性代码有望说明我正在尝试实现的目标:

I know that this won't work as written, but I'm struggling to see the right answer, and this non-functional code hopefully illustrates what I'm trying to achieve:

var defaults = _cilQueryContext.DefaultCharges
                    .Where(dc => dc.ChargingSchedule_RowId == cs.RowId);

List<DevelopmentType> devTypes = 
        defaults.Select(dc => dc.DevelopmentType)
                .Include(d => d.DefaultCharges)
                .Include(d => d.OverrideCharges.Where(oc => oc.ChargingSchedule_RowId == cs.RowId))
                .Include(d => d.OverrideCharges.Select(o => o.Zone))
                .ToList();

从本质上讲，我认为这需要一个联接，但是由于要选择包含两种相关类型子项的父对象，因此看不到联接的"select new"子句中会发生什么. /p>

Essentially, I had presumed this required a join, but seeing as I'm trying to select a parent object containing two related types of children, I can't see what would go in the join's "select new" clause.

推荐答案

据我所知，Include不支持此类子查询.最好的选择是使用投影，例如

As far as I am aware Include does not support this type of sub-querying. Your best option is to use projection e.g.

List<DevelopmentType> devTypes = 
           defaults.Include(x => x.DefaultCharges)
                   .Include(x => x.OverrideCharges)
                   .Select(x => new {
                        DevType = x.DevelopmentType,
                        Zones = x.OverrideCharges.Where(oc => oc.ChargingSchedule_RowId == cs.RowId)
                                                 .Select(oc => oc.Zone).ToList()
                   })
                   .Select(x => x.DevType)
                   .ToList();

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