我收到此错误,我试图解决它很长但无法修复它。 LINQ to Entities无法识别方法'System.Object Parse(System.Type,System.String)'方法,并且此方法无法转换为商店表达式。
public static List<itmCustomization> GetAllProductCustomziation(string catID)
{
var arrcatID = catID.Split('_');
int PId = int.Parse(arrcatID[0].ToString());
int CatID = int.Parse(arrcatID[1].ToString());
EposWebOrderEntities db = new EposWebOrderEntities();
List<itmCustomization> lstCust = new List<itmCustomization>();
lstCust.AddRange((from xx in db.vw_AllCustomization
where xx.CatID == CatID && xx.ProductID == PID
select new itmCustomization()
{
itmName = xx.Description,
catId = (int)xx.CatID,
proId = (int)xx.ProductID,
custType = (customizationType)Enum.Parse(typeof(customizationType), xx.CustType)
}).ToList<itmCustomization>());
return lstCust;
}
答案 0 :(得分:13)
当您使用LINQ To Entities时,Entity Framework目前正在尝试将Enum.Parse
转换为SQL,但它失败了,因为它不是受支持的函数。
在调用Enum.Parse
之前,您可以做的是实现SQL请求:
lstCust.AddRange((from xx in db.vw_AllCustomization
where xx.CatID == CatID && xx.ProductID == PID
select xx)
.TolList() // Moves to LINQ To Object here
.Select(xx => new itmCustomization()
{
itmName = xx.Description,
catId = (int)xx.CatID,
proId = (int)xx.ProductID,
custType = (customizationType)Enum.Parse(typeof(customizationType), xx.CustType)
}).ToList<itmCustomization>());
答案 1 :(得分:2)
我认为这个错误正在引发custType = (customizationType)Enum.Parse(typeof(customizationType), xx.CustType)
。 BTW是什么类型的xx.CustType?我认为它返回字符串,但预期的类型是枚举,这就是它抛出此错误的原因。