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PODataProvider Switch / Singleton ?
 

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    <p>I have a website and want to step over from MySql to SqlServer. </p> <p>In my website I use a BE layer (Business Entities), BLL (Business Logic Layer), DAL (Data Access Layer), and of course a Web Layer (Website) </p> <p>I've created a switch in the web.config (app settings) to tell the website to use MySql or SqlServer as DataProvider. </p> <p>I use the folowing code.... which works perfectly, but my question is ... </p> <ul> <li>Is this the right way to use a multi DAL tier?</li> <li>Is this thread Safe ? or I have to implement Singleton at the Factory class ?</li> </ul> <p>Please let me know what you should do, or what your opionion is.</p> <pre><code>namespace MyNameSpace.BE { public class Product { public int Id { get; set; } public int Description { get; set; } } } namespace MyNameSpace.DAL.Base { public abstract class ProductManager { public abstract List&lt;Product&gt; GetProductList(); } } namespace MyNameSpace.DAL.MySql { public class ProductManager : Base.ProductManager { public override List&lt;Product&gt; GetProductList() { return new List&lt;Product&gt;(); } } } namespace MyNameSpace.DAL.SqlServer { public class ProductManager : Base.ProductManager { public override List&lt;Product&gt; GetProductList() { return new List&lt;Product&gt;(); } } } namespace MyNameSpace.Bll { /// do I have to use Singleton here ?? or not ? public static class Factory { private static ProductManager CreateProductManager() { if (Config.Settings.Switches.DataProvider == DataProvider.MySql) { return new DAL.MySql.ProductManager(); } else if (Config.Settings.Switches.DataProvider == DataProvider.SqlServer) { return new DAL.SqlServer.ProductManager(); } return null; } private static ProductManager _ProductManager; public static ProductManager ProductManager { get { if (_ProductManager == null) { _ProductManager = CreateProductManager(); } return _ProductManager; } } } } /// &lt;summary&gt; /// for example ASP.NET page /// &lt;/summary&gt; class MyPage { public MyPage() { List&lt;Product&gt; productList = Factory.ProductManager.GetProductList(); } } </code></pre>
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    1. USJames A Mohler
    1. USRuutert
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    1. COThis works but you can probably do the same thing using an IoC container to save you a few lines of code.
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      1. USThomas Li
 

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