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    <p>You can define a useful extension method ...</p> <pre><code>Type type = typeof(ProjectController); var attributes = type.GetCustomAttributes&lt;CustomDescriptionAttribute&gt;( true ); </code></pre> <p>Here is the extension method:</p> <pre><code>/// &lt;summary&gt;Searches and returns attributes. The inheritance chain is not used to find the attributes.&lt;/summary&gt; /// &lt;typeparam name="T"&gt;The type of attribute to search for.&lt;/typeparam&gt; /// &lt;param name="type"&gt;The type which is searched for the attributes.&lt;/param&gt; /// &lt;returns&gt;Returns all attributes.&lt;/returns&gt; public static T[] GetCustomAttributes&lt;T&gt;( this Type type ) where T : Attribute { return GetCustomAttributes( type, typeof( T ), false ).Select( arg =&gt; (T)arg ).ToArray(); } /// &lt;summary&gt;Searches and returns attributes.&lt;/summary&gt; /// &lt;typeparam name="T"&gt;The type of attribute to search for.&lt;/typeparam&gt; /// &lt;param name="type"&gt;The type which is searched for the attributes.&lt;/param&gt; /// &lt;param name="inherit"&gt;Specifies whether to search this member's inheritance chain to find the attributes. Interfaces will be searched, too.&lt;/param&gt; /// &lt;returns&gt;Returns all attributes.&lt;/returns&gt; public static T[] GetCustomAttributes&lt;T&gt;( this Type type, bool inherit ) where T : Attribute { return GetCustomAttributes( type, typeof( T ), inherit ).Select( arg =&gt; (T)arg ).ToArray(); } /// &lt;summary&gt;Private helper for searching attributes.&lt;/summary&gt; /// &lt;param name="type"&gt;The type which is searched for the attribute.&lt;/param&gt; /// &lt;param name="attributeType"&gt;The type of attribute to search for.&lt;/param&gt; /// &lt;param name="inherit"&gt;Specifies whether to search this member's inheritance chain to find the attribute. Interfaces will be searched, too.&lt;/param&gt; /// &lt;returns&gt;An array that contains all the custom attributes, or an array with zero elements if no attributes are defined.&lt;/returns&gt; private static object[] GetCustomAttributes( Type type, Type attributeType, bool inherit ) { if( !inherit ) { return type.GetCustomAttributes( attributeType, false ); } var attributeCollection = new Collection&lt;object&gt;(); var baseType = type; do { baseType.GetCustomAttributes( attributeType, true ).Apply( attributeCollection.Add ); baseType = baseType.BaseType; } while( baseType != null ); foreach( var interfaceType in type.GetInterfaces() ) { GetCustomAttributes( interfaceType, attributeType, true ).Apply( attributeCollection.Add ); } var attributeArray = new object[attributeCollection.Count]; attributeCollection.CopyTo( attributeArray, 0 ); return attributeArray; } /// &lt;summary&gt;Applies a function to every element of the list.&lt;/summary&gt; private static void Apply&lt;T&gt;( this IEnumerable&lt;T&gt; enumerable, Action&lt;T&gt; function ) { foreach( var item in enumerable ) { function.Invoke( item ); } } </code></pre> <p><strong>Update:</strong></p> <p>Here is a shorter version as proposed by SimonD in a comment:</p> <pre><code>private static IEnumerable&lt;T&gt; GetCustomAttributesIncludingBaseInterfaces&lt;T&gt;(this Type type) { var attributeType = typeof(T); return type.GetCustomAttributes(attributeType, true). Union(type.GetInterfaces(). SelectMany(interfaceType =&gt; interfaceType.GetCustomAttributes(attributeType, true))). Distinct().Cast&lt;T&gt;(); } </code></pre>
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    1. POCan a C# class inherit attributes from its interface?
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    1. COThis only gets type-level attributes, not properties, fields or members, right?
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    2. COvery nice, I personally use a shorter version of this, now: private static IEnumerable<T> GetCustomAttributesIncludingBaseInterfaces<T>(this Type type) { var attributeType = typeof(T); return type.GetCustomAttributes(attributeType, true).Union(type.GetInterfaces().SelectMany(interfaceType => interfaceType.GetCustomAttributes(attributeType, true))).Distinct().Cast<T>(); }
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      1. USSimon D.
    3. CO@SimonD.: And your refactored solution is faster.
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