Entity Framework Core Include/ThenInclude 获取数据

Question

I have tables in my database with the following one-to-many relations:我的数据库中有以下一对多关系的表：

a -> b
b -> c
b -> d

which are mapped to corresponding navigational properties in the model.它们映射到 model 中的相应导航属性。

I want to get data from "a" with all related data from "b, c, d".我想从“a”获取数据以及“b，c，d”的所有相关数据。

If I try:如果我尝试：

dbcontext.a.Include(x => x.b)
           .ThenInclude(x => x.c)
           .ThenInclude(x => x.d)

I get an error because this implies a relationship c -> d (instead of b -> d ).我收到一个错误，因为这意味着关系c -> d （而不是b -> d ）。

Then, if I try:然后，如果我尝试：

dbcontext.a.Include(x => x.b)
           .ThenInclude(x => x.c)
           .Include(x => x.d)

I get an error because this implies a relationship a -> d (instead of b -> d ).我收到一个错误，因为这意味着关系a -> d （而不是b -> d ）。

I'd appreciate help on how to correctly chain the methods.我很感激有关如何正确链接方法的帮助。

Answer 1

Try this if you use net5如果你使用 net5 试试这个

dbcontext.a.Include(x => x.b)
            .ThenInclude(x => x.c)
             .Include(x => x.b)
            .ThenInclude(x => x.d)

Or to avoid repeating you can try ( was tested by @Marko )或者为了避免重复，您可以尝试（由@Marko 测试）

dbcontext.a.Include(x => x.b)
            .ThenInclude(x => x.c)
             .Include(x => x.b.d)

but I prefer to use this syntax (fits for all versions)但我更喜欢使用这种语法（适用于所有版本）

dbcontext.a.Include(x => x.b)
            .ThenInclude(x => x.c)
             .Include("b.d")