Databases
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    <p>One thing you could do is create a factory for the <code>DatabaseManager</code> and then just have all your other code call it from that factory. I'm very out of practice with VB syntax, but in C# it might look something like this:</p> <pre><code>public class DatabaseManagerFactory { private static DatabaseManager _current = null; public static DatabaseManager Current { get { if (_current == null) _current = new DatabaseManager(); return _current; } } } </code></pre> <p>VB</p> <pre><code>Public Class DatabaseManagerFactory Private Shared _current As DatabaseManager = Nothing Public Shared ReadOnly Property Current As DatabaseManager Get If _current Is Nothing null Then _current = New DatabaseManager() Return _current End Get End Property End Class </code></pre> <p>The idea then is that anything in your application which needs to use a <code>DatabaseManager</code> would just call <code>DatabaseManagerFactory.Current</code> to get the one shared instance.</p> <p>Note that in this case <code>DatabaseManager</code> isn't really a singleton, you can still instantiate one elsewhere in the application if you need to for some reason. If it should be an actual singleton then you'd want to make some modifications to the <code>DatabaseManager</code> class itself. Maybe give it a private constructor and implement this factory directly on the class? Something like this:</p> <pre><code>public class DatabaseManager { private static DatabaseManager _current = null; public static DatabaseManager Current { get { if (_current == null) _current = new DatabaseManager(); return _current; } } private DatabaseManager { // your initialization of the class } } </code></pre> <p>VB</p> <pre><code>Public Class DatabaseManager Private Shared _current DatabaseManager = Nothing Public Shared ReadOnly Property Current As DatabaseManager Get If _current Is Nothing Then _current = New DatabaseManager() Return _current End Get End Property Private Sub New() ' your initialization of the class End Sub End Class </code></pre> <p>(I encourage anybody more familiar with VB syntax to edit this answer accordingly to better address the question.)</p>
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    1. COI added the VB as you requested.
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    2. CO@chrissie1: Thanks! I agree with your answer as well, using DI. (My personal tool of choice for that is StructureMap.) A mix of the two will work as well, just replacing `new DatabaseManager()` in mine with a call to the DI container to resolve the dependency. I particularly like to do this when the DI container is abstracted behind a service locator, just in case a later IoC implementation doesn't support constructor injection or setter injection, etc. Naturally, as with anything, there are many approaches to take.
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    3. COyup, factories have their place together with DI/IoC.
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