Base class for subsonic data access files, just inherit this class (rename the db type to match your own), provide the subsonic entity type. Has deps on subsonic and richmondday.helpers

ServiceBase.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

using CollectBruceLee;
using CollectBruceLee.Data;

using RichmondDay.Helpers;

using SubSonic.Query;
using SubSonic.Repository;

public abstract class ServiceBase<T> where T :class, new() {
    protected virtual double CacheExpiry {
        get { return 60;}
    } // time in seconds the cache should live for

    protected abstract string CacheKey {
        get;
    } // a unique way to identify the item in the cache

    protected CacheHelper CacheHelper;

    protected IQuerySurface db;

    public ServiceBase() {
        if(db == null) db = new ServiceLocator().GetService<IQuerySurface>();

        if (App.CachingEnabled) {
            if (CacheHelper == null) CacheHelper = new CacheHelper(HttpContext.Current.Cache);
        } // a good place to put App.CachingEnabled is in your Global.asax.cs
    }

    public ServiceBase(IQuerySurface _db) {
        // should do something serious if _db is null.
        if (db == null) db = _db; // change this to match your concrete implementation
            
        if (App.CachingEnabled) {
            if (CacheHelper == null) CacheHelper = new CacheHelper(HttpContext.Current.Cache);
        } // a good place to put App.CachingEnabled is in your Global.asax.cs
    }

    protected SubSonicRepository<T> GetRepository<T>() where T : class, new() {
        return new SubSonicRepository<T>(db);
    }

    protected virtual List<T> GetData() {
        List<T> data = CacheHelper != null && CacheExpiry > 0 ? CacheHelper.Get(CacheKey) as List<T> : null;

        if (data == null) {
            data = GetRepository<T>().GetAll().ToList();
            if (CacheHelper != null)
                CacheHelper.Add(CacheKey, data, DateTime.Now.AddSeconds(CacheExpiry));
        }

        return data;
    }

    public virtual void Delete(int id) {
        GetRepository<T>().Delete(id);
    }
}

/// <summary>
/// started doing this based on these posts
/// http://stefanoricciardi.com/2009/10/29/a-singleton-service-locator-pattern/
/// http://stefanoricciardi.com/2009/10/13/service-locator-pattern-in-c-with-lazy-initialization/
/// </summary>
interface IServiceLocator {
    T GetService<T>();
}
class ServiceLocator : IServiceLocator {
    private IDictionary<object, object> services;

    internal ServiceLocator() {
        services = new Dictionary<object, object>();
        this.services.Add(typeof(IQuerySurface), new CollectBruceLeeDB());
    }

    public T GetService<T>() {
        try {
            return (T)services[typeof(T)];
        } catch (KeyNotFoundException) {
            throw new ApplicationException("The requested service is not registered");
        }
    }
}