Question

I have the following code that worked before I changed to use generics for the service:

Update: I added some more class and interface info in response to comments:

public class Service<T1,T2> : BaseService, IService<T1>
        where T1 : IAuditableTable
        where T2 : IAuditableTable
{
    private IAzureTable<T1> _T1repository;
    private IAzureTable<T2> _T2repository;

    public Service(string ds)
    {
        base.Initialize(ds);
        _T1repository = StorageHelper.GetTable<T1>(ds);
        _T2repository = StorageHelper.GetTable<T2>(ds);
    }

    public IEnumerable<AdminDetail> ShowDetails()
    {
        return base.ShowDetails(_T1repository, _T2repository);
    } 

    ...

and

public IEnumerable<AdminSummary> ShowSummary<T1, T2>(
        IAzureTable<T1> master, IAzureTable<T2> detail)
    where T1 : AuditableTable
    where T2 : AuditableTable
{
    ...

public abstract class AuditableTable : TableServiceEntity, IAuditableTable  
{
    ...

public interface IAzureTable<T> : IInitializer

public interface IService<T>
        where T : IAuditableTable
    {
        IEnumerable<AdminSummary> ShowSummary();
    }

private IService<Account> _account;
vm.AdminSummaries = _account.ShowSummary(); << calls the report

When I try to compile I get the following message:

The type ‘T2’ cannot be used as type parameter ‘T2’ in the generic type or
method ‘Services.BaseService.ShowSummary<T1,T2>(AzureToolkit.IAzureTable<T1>, AzureToolkit.IAzureTable<T2>)’. There is no boxing conversion or type parameter conversion from ‘T2’ to ‘Storage.Models.AuditableTable’.

Answer 1

You might need the class constraint on T2.