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    <p>This is not possible in any .NET language because of type-safety concerns. In type-safe languages, you must provide covariance for return values, and contravariance for parameters. Take this code:</p> <pre><code>class B { S Get(); Set(S); } class D : B { T Get(); Set(T); } </code></pre> <p>For the <code>Get</code> methods, covariance means that <code>T</code> must either be <code>S</code> or a type derived from <code>S</code>. Otherwise, if you had a reference to an object of type <code>D</code> stored in a variable typed <code>B</code>, when you called <code>B.Get()</code> you wouldn't get an object representable as an <code>S</code> back -- breaking the type system.</p> <p>For the <code>Set</code> methods, contravariance means that <code>T</code> must either be <code>S</code> or a type that <code>S</code> derives from. Otherwise, if you had a reference to an object of type <code>D</code> stored in a variable typed <code>B</code>, when you called <code>B.Set(X)</code>, where <code>X</code> was of type <code>S</code> but not of type <code>T</code>, <code>D::Set(T)</code> would get an object of a type it did not expect.</p> <p>In C#, there was a conscious decision to disallow changing the type when overloading properties, even when they have only one of the getter/setter pair, because it would otherwise have very inconsistent behavior (<em>"You mean, I can change the type on the one with a getter, but not one with both a getter and setter? Why not?!?"</em> -- Anonymous Alternate Universe Newbie).</p>
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    1. USAlex Lyman
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    1. COYour point is valid, but the example had a read-only property.
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      1. USAnthony
    2. COPerfectly demonstrated!
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      1. USLuis Filipe
 

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A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

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