匿名类型不能具有多个具有相同名称的属性

Question

我想通过实体框架绑定gridview,但它会抛出错误,如 -

匿名类型不能具有同名Entity Framwrok的多个属性

这是我的方法.

public void UserList(GridView grdUserList)
{
    using (TreDbEntities context = new TreDbEntities())
    {

        var query =( from m in context.aspnet_Membership
                    from u in context.aspnet_Users
                    join usr in context.Users
                    on new { m.UserId, u.UserId } 
                    equals new { usr.MembershipUserID, usr.UserId }
                    into UserDetails
                    from usr in UserDetails
                    select new { 
                       CreationDate = m.CreateDate,
                       email = m.Email,
                       UserName = u.LoweredUserName,
                       Name = usr.FirstName + usr.LastNameLastName,
                       Active=usr.IsActive
                    }).ToList();
    }
}

它在这里显示错误.usr.UserId.

Answer 1

直接问题是匿名类型new { m.UserId, u.UserId }:同名两次.您可以通过提供显式属性名称来解决此问题,例如:new { u1 = m.UserId, u2 = u.UserId }.

但接下来的问题是,定义连接的两个匿名类型都不会具有相同的属性名称,因此最终修复是这样的:

public void UserList(GridView grdUserList)
{
    using (TreDbEntities context = new TreDbEntities())
    {
        var query =( from m in context.aspnet_Membership
                    from u in context.aspnet_Users
                    join usr in context.Users
                    on new { u1 = m.UserId, u2 = u.UserId } 
                    equals new { u1 = usr.MembershipUserID, u2 = usr.UserId }
                    into UserDetails
                    from usr in UserDetails
                    select new { CreationDate = m.CreateDate,
                                 email = m.Email,
                                 UserName = u.LoweredUserName,
                                 Name = usr.FirstName + " " + usr.LastName,
                                 Active = usr.IsActive
                               }
                   ).ToList();
    }
}

Answer 2

@Gert答案是对的.只想显示更简单的解决方案 - 仅为第一个UserId属性命名:

on new { MembershipUserID = m.UserId, u.UserId }