在父子关系中具有多个对象的Linq查询

var pck = content.Package
     // Outdented just for Stack Overflow\'s width
     .Where(pk => pk.Lists.Any(list => list.Any(u => u.UserId == myUserId)));

var pck = from pk in content.Package
          from list in pk.Lists
          from user in list.Users
          where user.UserId == myUserId
          select ...; // Select whatever you\'re interested in

context.Packages.Where(p => p.Lists.Any(l => l.Users.Contains(MyUserId)))

context.Packages.Where(p => p.Lists.Any(l => l.Users.Any(u => u.Id == MyUserId)))

var packages =
    context.Package.Where(p =>
        p.Lists.Any(l => 
            l.Users.Any(u => u.UserId == MyUserId
        )
    );

var pck = from user in context.Users
          where user.UserId == userId
          select user.List.Package;

pk.Lists.Any(l => l.Users.Any(u => u.UserId == MyUserId))