如何使用Lambda表达式查询嵌套列表 [英] How to query a nested list using a lambda expression

问题描述

在我的存储库实现中，我可以使用lambda表达式运行以下查询:

In my repository implementation I can run the following query using a lambda expression:

public IList<User> GetUsersFromCountry(string)
{
    return _UserRepository.Where(x => x.Country == "Sweden").ToList();                  
}

到目前为止，还不错，很简单.但是，我很难针对嵌套->嵌套列表编写lambda表达式.给出以下示例(对不起，想不到更好的示例):

So far so good, simple stuff. However, I'm having difficulties to write a lambda expression against a nested -> nested list. Given the following example (sorry couldn't think of a better one):

以下查询绝对可以正常工作，并返回会员年龄超过45岁的所有俱乐部

The following query works absolutely fine and returns all clubs, which have members over the age of 45

public IList<Clubs> GetGoldMembers()
        {
            var clubs =   from c in ClubRepository
                          from m in c.Memberships 
                          where m.User.Age  >  45
                          select c;

            return clubs;
        }

此刻，我对lambda表达的了解到此结束.

At the moment, this is where my knowledge of lambda expression ends.

如何使用类似于上面的示例的lambda表达式针对ClubRepository编写上述查询?

How could I write the above query against the ClubRepository, using a lambda expression, similar to the example above?

推荐答案

这可能有效(未经测试)...

This might work (untested)...

var clubs = ClubRepository.Where(c=>c.MemberShips.Any(m=>m.User.Age > 45));

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