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PODeriving from Control but hiding properties
 

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    <p>Yes, I am aware this has been asked and answered before, but nothing fully addresses several issues.</p> <p><strong>References</strong></p> <ul> <li><a href="https://stackoverflow.com/questions/1528/hiding-inherited-members-in-c">Hiding inherited members</a></li> <li><a href="https://stackoverflow.com/questions/1528371/hiding-unwanted-properties-in-custom-controls">Hiding unwanted properties in custom controls</a></li> </ul> <p>Essentially, I'd like to derive from <code>Control</code> but without exposing certain properties. In my case, I am designing a <code>Container</code>, which will contain many <code>Element</code>s, arranged in a programmatic way. I'd like (and may <em>require</em>) that <code>Element</code> derives from <code>Control</code>, in order to get all of the drawing and events, but also be able to add <code>Element</code> objects to the <code>Container</code>'s <code>Children</code> collection (for obvious reasons).</p> <p>The only problem is, if <code>Element</code> derives from <code>Control</code>, then its <code>Location</code> property is exposed, and the user could easily destroy the programmatic placement. Naturally, my instinct is to keep all the goodies that come along with <code>Control</code> and hide/disable the <code>Location</code>.</p> <p>I'm aware of the following:</p> <ul> <li>This violates the SOLID Liskov substitution principle (design by contract)</li> <li>This has been asked before</li> <li>I could encapsulate <code>Control</code> in my <code>Element</code> and forward all of the calls to those of <code>Control</code> <ul> <li>This would be a ridiculous amount of work, and for no real gain.</li> <li>The encapsulating <code>Element</code> would still not be type-compatible with <code>Control</code> and could not be used in many cases where a derived form of <code>Control</code> would.</li> </ul></li> </ul> <p>I feel there must be some more elegant solution to this (seemingly) recurring problem. Thank you in advance!</p> <p><strong>Edit</strong></p> <p>The only way I see to accomplish this is:</p> <pre><code>public class Element : Control { public new Point Location { get; private set; } } </code></pre> <p>But then, I have the problem of, how does my container class set the <code>Element</code>s location? In C++ one would use a friend class. I suppose if I kept this control in its own assembly, I could mark the setter as <code>internal</code>.</p> <p><strong>Edit</strong></p> <p>For those looking to do something this, my solution was: to not do it. Instead, I made a custom object and implemented all of the clicking / dragging, etc myself. It was just too complicated to try and use a Control, while excluding functionality like Location.</p>
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