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POUsing Enum as/with expressions?
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  1. POUsing Enum as/with expressions?
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    copied!<p>Is it possible to use an enum with expressions to reflect on the enum values? Consider this <em>hypothetical</em> routine:</p> <pre><code>public enum Fruit { Apple, Pear } public void Foo(Fruit fruit) { Foo&lt;Fruit&gt;(() =&gt; fruit); } public void Foo&lt;T&gt;(Expression&lt;Func&lt;T&gt;&gt; expression) { //... example: work with Fruit.Pear and reflect on it } </code></pre> <p><code>Bar()</code> will give me information about the enum, but I want to work with the actual value.</p> <p>Background: I've been adding some helper methods to return CustomAttribute information for types and wondered if a similar routine could be used for enums.</p> <p>I'm fully aware you can work with the enum type to get the CustomAttributes that way.</p> <p><strong>Update:</strong></p> <p>I use a similar concept in MVC with helper extensions:</p> <pre><code>public class HtmlHelper&lt;TModel&gt; : System.Web.Mvc.HtmlHelper&lt;TModel&gt; { public void BeginLabelFor&lt;TProperty&gt;(Expression&lt;Func&lt;TModel, TProperty&gt;&gt; expression) { string name = ExpressionHelper.GetExpressionText(expression); } } </code></pre> <p>In this example <code>name</code> would be the member name of the model. I want to do a similar thing with enums, so name would be the enum 'member'. Is this even possible?</p> <p><strong>Updated example:</strong></p> <pre><code>public enum Fruit { [Description("I am a pear")] Pear } public void ARoutine(Fruit fruit) { GetEnumDescription(() =&gt; fruit); // returns "I am a pear" } public string GetEnumDescription&lt;T&gt;(/* what would this be in a form of expression? Expression&lt;T&gt;? */) { MemberInfo memberInfo; // a routine to get the MemberInfo(?) 'Pear' from Fruit - is this even possible? if (memberInfo != null) { return memberInfo.GetCustomAttribute&lt;DescriptionAttribute&gt;().Description; } return null; // not found or no description } </code></pre>
 

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