相关疑难解决方法(0)

我有以下枚举定义(在C#中):

public enum ELogLevel
{
    General = -1,  // Should only be used in drop-down box in Merlinia Administrator log settings
    All = 0,       // Should not be used as a level, only as a threshold, effectively same as Trace
    Trace = 1,
    Debug = 2,
    Info = 3,
    Warn = 4,
    Error = 5,
    Fatal = 6,
    Off = 7        // Should not be used as a level, only as a threshold
}

现在,当我Enum.GetNames()在这个类型上做一个我得到一个包含9个元素的字符串数组,但顺序是All,Trace,...,Off,General,这不是我所期待的.

下面是MSDN 文档为 …

我尝试在nopCommerce 3.0中创建一个linq连接查询.我加入linq的两张桌子并写下来

代码成功了.但视觉工作室的知识分子显示出错误

具有语句主体的lambda表达式无法转换为表达式树

请看下面的代码

 var roles = _customerEventRoleRepository.Table.Where(c => c.EventId == selevent)
                   .Join
                   (
                      _customerRepository.Table,
                      cev => cev.CustomerId, c => c.Id,
                      (cev, c) =>
                      {                             
                          var cust = new CustomerEventRolesModel();

                          cust.Id = cev.Id;
                          cust.CustomerId = c.Id;
                          cust.Customer = c.Email;
                          cust.ContactName = c.GetAttribute<string>(SystemCustomerAttributeNames.FirstName);
                          cust.CompanyName = c.GetAttribute<string>(SystemCustomerAttributeNames.Company);
                          cust.Speaker = cev.IsSpeaker;
                          cust.Sponsor = cev.IsSponser;

                          return cust;
                      }
                    ).OrderBy(cev => cev.Customer).ToList();

但错误显示

请帮忙