Enterprise Application Architecture with LINQ to SQL

using System;
using System.Data;
using System.Configuration;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

using Northwind.Business;
using Northwind.Business.DataInterfaces;
using Northwind.Data.DTO;
using System.Collections.Generic;
using System.Text.RegularExpressions;
using System.Reflection;

/*
 **************************************************************
 * Author: Rohit Gadagkar (rohit.gadagkar@gmail.com)
 * Copyright � 2007 Rohit Gadagkar
 * License:
 * Free without any restrictions whatsoever 
 *
 * Created: 9/1/2007
 * 
 * THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY
 * OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT
 * LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
 * FITNESS FOR A PARTICULAR PURPOSE.
 **************************************************************  
*/

/// <summary>
/// Summary description for Util
/// </summary>
public static class Util
{
    class Constants
    {
        public const string DAO_FACTORY_KEY = "daoFactoryType";
        public const string DEFAULT_FACTORY_TYPE = "Northwind.Data.DLinqDAOFactory";
        public const string FACTORY_ASSEMBLY = "Northwind.Data";
        public const string CACHED_PROP_PREFIX = "__$DTOProperty_";        
    }

    public static T MarshalObject<T>(FormView f) where T:new()
    {
        T dto = new T();
        Type type = dto.GetType();
        for (int i = 0; i < f.Row.Cells[0].Controls.Count; i += 2)
        {
            Control label = f.Row.Cells[0].Controls[i];
            if (label is LiteralControl)
            {
                string propName = (label as LiteralControl).Text;
                propName = Regex.Replace(propName, "([\\s:-]*(<br[ ]*/>)*)(\\w+)([\\s:-])+", "$3");
                if (!String.IsNullOrEmpty(propName))
                {
                    PropertyInfo prop = GetProperty(propName, type);
                    if (prop != null)
                    {
                        Control valueCell = f.Row.Cells[0].Controls[i + 1];
                        object value = (valueCell is TextBox)
                            ? (valueCell as TextBox).Text
                            : null;
                        prop.SetValue(dto, value, null);
                    }
                }
            }
        }
        return dto;
    }

    public static IDaoFactory CreateFactoryInstance()
    {
        string typeStr = ConfigurationManager.AppSettings[Constants.DAO_FACTORY_KEY];
        if (String.IsNullOrEmpty(typeStr)) typeStr = Constants.DEFAULT_FACTORY_TYPE;
        IDaoFactory f = null;
        try {
            Assembly a = Assembly.Load(Constants.FACTORY_ASSEMBLY);
            if (a != null) {
                Type fType = a.GetType(typeStr);
                if (fType == null) fType = a.GetType(String.Format("{0}.{1}",
                     Constants.FACTORY_ASSEMBLY, typeStr));
                f = Activator.CreateInstance(fType) as IDaoFactory;
            }
        }
        catch (Exception ex) {
            throw new Exception(String.Format("Unable to load {0} from Northwind.Data",
                      typeStr), ex);
        }
        return f;
    }

    internal static PropertyInfo GetProperty(string propName, Type type)
    {
        System.Web.Caching.Cache c = HttpRuntime.Cache;
        PropertyInfo prop = c[GetKey(propName)] as PropertyInfo;
        if (prop == null) {
            prop = type.GetProperty(propName);
            if(prop != null)    c[GetKey(propName)] = prop;
        }
        return prop;
    }

    internal static string GetKey(string propName)
    {
        return Constants.CACHED_PROP_PREFIX + propName;
    }

}