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POGenerics, Inheritance and the new operator
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  1. POGenerics, Inheritance and the new operator
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    copied!<p>Here is something that I find myself using from time to time and I just wanted to get some feedback on the merits of the practice.</p> <p>Lets say that I have a base class:</p> <pre><code>abstract class RealBase { protected RealBase(object arg) { Arg = arg; } public object Arg { get; private set; } public abstract void DoThatThingYouDo(); } </code></pre> <p>I often create a second base class that is generic that handles the cast from the "object" type in the base class to the "T" type, like this:</p> <pre><code>abstract class GenericBase&lt;T&gt; : RealBase { protected GenericBase(T arg) : base( arg ) { } new public T Arg { get { return (T) base.Arg; } } } </code></pre> <p>This allows me to access "Arg" as its explicit type without a cast operation: </p> <pre><code>class Concrete : GenericBase&lt;string&gt; { public Concrete( string arg ) : base( arg ) { } public override void DoThatThingYouDo() { // NOTE: Arg is type string. No cast necessary. char[] chars = Arg.ToLowerInvariant().ToCharArray(); // Blah( blah, blah ); // [...] } } </code></pre> <p>All the while being able to also work with it via the "RealBase":</p> <pre><code>class Usage { public void UseIt() { RealBase rb = new Concrete( "The String Arg" ); DoTheThing(rb); } private void DoTheThing(RealBase thingDoer) { rb.DoThatThingYouDo(); } } </code></pre> <p>It is assumed that there are many other "Concrete" types... not just the one.</p> <p>Here are my questions/concerns:</p> <ol> <li>Am I "off my rocker" for using an approach like this? </li> <li>Are there any obvious drawbacks/caveats to using this approach? </li> <li>What about that "new public T..." in GenericBase? Good/bad idea? Awkward?</li> </ol> <p>Any feedback or advice would be greatly appreciated.</p>
 

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