使用"where":无法将lambda表达式转换为'bool'类型

Question

我有实体框架代码,如下所示.我在where条件中得到以下错误.

无法将lambda表达式转换为类型'bool',因为它不是委托类型

如何克服这个错误？这个错误的原因是什么？

    static void Main(string[] args)
    {

        ClubCreation();
        List<Club> selectedClubs = GetClubs("club1");

    }

    public static void ClubCreation()
    {

        string connectionstring = "Data Source=.;Initial Catalog=NerdDinners;Integrated Security=True;Connect Timeout=30";
        using (var db = new NerdDinners(connectionstring))
        {

            Club club1 = new Club();
            club1.ClubName = "club1";

            Club club2 = new Club();
            club2.ClubName = "club2";

            Club club3 = new Club();
            club3.ClubName = "club3";

            db.Clubs.Add(club1);
            db.Clubs.Add(club2);
            db.Clubs.Add(club3);

            int recordsAffected = db.SaveChanges();


        }
    }

    public static List<Club> GetClubs(string clubName)
    {
        string connectionstring = "Data Source=.;Initial Catalog=NerdDinners;Integrated Security=True;Connect Timeout=30";
        using (var db = new NerdDinners(connectionstring))
        {

            Club club1 = new Club();
            Club club2 = new Club();
            Club club3 = new Club();


            var query = from o in db.Clubs
                        where (p => p.ClubName == "club1")
                        select o;

            return query.ToList();





        }
    }

Answer 1

而不是where (p => p.ClubName == "club1")使用:

var query = from o in db.Clubs
            where  o.ClubName == "club1"
            select o;

可能是你与方法链接混淆的地方:

var query = db.Clubs.Where(p => p.ClubName == "club1");