我收到以下错误：
Unable to create a constant value of
type
‘Phoenix.Intranet.Web.ClientSettings.ComponentRole’.
Only primitive types (‘such as Int32,
String,and Guid’) are supported in
this context.
我明白为什么错误发生.我不明白的是为什么我的代码创建错误.我的比较是反对原始类型.所有比较都是Guid to Guid.该错误明确指出,圭ids是好的.
该行发生错误(向下)：
var vla = (from cir in phoenixEntities.ComponentInRoles
码：
List<ComponentRole> roles;
using (IMSMembershipEntities entities = new IMSMembershipEntities())
{
roles = (from role1 in entities.Roles
select new ComponentRole{Name = role1.RoleName,RoleId = role1.RoleId} ).ToList();
}
List<Components> componentInRoles;
using (PhoenixEntities phoenixEntities = new PhoenixEntities())
{
phoenixEntities.ContextOptions.LazyLoadingEnabled = false;
componentInRoles = (from component in phoenixEntities.Components
select new Components{Name = component.Name,ComponentId = component.ComponentId,//InRoles = (from componentInRole in phoenixEntities.ComponentInRoles
// join role in roles on componentInRole.RoleId equals role.RoleId
// where componentInRole.ComponentId == component.ComponentId
// select new ComponentRole{RoleId = role.RoleId,Name = role.Name})
}
).ToList();
foreach (Components cmpent in componentInRoles)
{
Components cmpent1 = cmpent;
//cmpent.InRoles =
var vla = (from cir in phoenixEntities.ComponentInRoles
join role in roles on cir.RoleId equals role.RoleId
where cir.ComponentId == cmpent1.ComponentId
select role).ToList();
}
}
解决方法
EntityFramework和Linq to sql都尝试将这样的查询转换为sql IN操作符,这些查询是内存中的一部分,另一部分在数据库中.
并且因为你的类哪个角色是一个IEnumerable是不是一个原始类型,它不能被翻译成SQL查询.
例如：
var vla = (from cir in phoenixEntities.ComponentInRoles.ToList()
join role in roles on cir.RoleId equals role.RoleId
where cir.ComponentId == cmpent1.ComponentId
select role).ToList();
我希望我能帮忙
