我从BankAccount类派生两个类 - FixedBankAccount和SavingsBankAccount。这是工作的基础上TPH(表每层次)使用LINQ到SQL。
[全球:: System.Data.Linq.Mapping.TableAttribute(NAME =dbo.BankAccount)
[InheritanceMapping(code =固定,类型= typeof运算(FixedBankAccount),ISDEFAULT =真)
[InheritanceMapping(code =储蓄,类型= typeof运算(SavingsBankAccount))]
公共抽象部分类的BankAccount:INotifyPropertyChanging,INotifyPropertyChanged的
我需要实现的方法GetAllAccountsOfType将返回所有SavingsBankAccount(如果传递的类型是SavingsBankAccount)或FixedBankAccounts(如果传递的类型是FixedBankAccount)。我得到的错误:
中的类型或命名空间名称'参数'找不到
与下面的code(使用OfType对LINQ查询)
我们怎样才能使它工作?
存储库:
命名空间RepositoryLayer
{
公共类LijosSimpleBankRepository:ILijosBankRepository
{
公共System.Data.Linq.DataContext上下文{获得;组; }
公共虚拟目录< DBML_Project.BankAccount> GetAllAccountsOfType(DBML_Project.BankAccount参数)
{
VAR的查询=从p在Context.GetTable< DBML_Project.BankAccount>()OfType<参数>()
选择磷;
}
}
}
解决方案
声明:
公开的IEnumerable< T> GetAllAccounts< T>()
其中,T:BankAccount的// T必须继承类的BankAccount,像你的两个子类做
{
返回Context.GetTable< DBML_Project.BankAccount>()OfType< T>();
}
用法:
VAR allSaving = GetAllAccounts< SavingsBankAccount>();
变种allFixed = GetAllAccounts&其中; FixedBankAccount>();
I have two classes derived from BankAccount class – FixedBankAccount and SavingsBankAccount. This is working based on "TPH (Table Per Hierarchy)" with LINQ to SQL.
[global::System.Data.Linq.Mapping.TableAttribute(Name="dbo.BankAccount")]
[InheritanceMapping(Code = "Fixed", Type = typeof(FixedBankAccount), IsDefault = true)]
[InheritanceMapping(Code = "Savings", Type = typeof(SavingsBankAccount))]
public abstract partial class BankAccount : INotifyPropertyChanging, INotifyPropertyChanged
I need to implement a method GetAllAccountsOfType which will return all the SavingsBankAccount (if the type passed is SavingsBankAccount) or FixedBankAccounts (if the type passed is FixedBankAccount). I am getting error:
The type or namespace name 'param' could not be found"
with the following code (which uses "OfType" on LINQ query)
How can we make it working?
Repository:
namespace RepositoryLayer
{
public class LijosSimpleBankRepository : ILijosBankRepository
{
public System.Data.Linq.DataContext Context { get; set; }
public virtual List<DBML_Project.BankAccount> GetAllAccountsOfType(DBML_Project.BankAccount param)
{
var query = from p in Context.GetTable<DBML_Project.BankAccount>().OfType<param>()
select p;
}
}
}
解决方案
Declaration:
public IEnumerable<T> GetAllAccounts<T>()
where T : BankAccount // T must inherit class BankAccount, like your two sub-classes do
{
return Context.GetTable<DBML_Project.BankAccount>().OfType<T>();
}
Usage:
var allSaving = GetAllAccounts<SavingsBankAccount>();
var allFixed = GetAllAccounts<FixedBankAccount>();