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    <p>Enum types are distinct, but you're being confused by an implicit cast which is in foreach.</p> <p>Let's rewrite your loop a bit:</p> <pre><code>public static void Main() { List&lt;Cars&gt; cars = new List&lt;Cars&gt;(); List&lt;Animals&gt; animals = new List&lt;Animals&gt;(); cars.Add(Cars.Chevrolet); cars.Add(Cars.Honda); cars.Add(Cars.Toyota); foreach (Cars value in cars) { // This time the cast is explicit. Animals isItACar = (Animals) value; Console.WriteLine(isItACar.ToString()); } Console.ReadLine(); } </code></pre> <p>Now does the result surprise you? Hopefully not, except possibly the fact that you <em>can</em> cast from one enum to another. This is just a more explicit version of what your original code is doing.</p> <p>The fact that there's a cast implicit in every <code>foreach</code> loop (even though it's usually a no-op) is the bit which most developers would find confusing, I think.</p> <p>From section 8.8.4 of the C# 3.0 spec:</p> <blockquote> <p>The above steps, if successful, unambiguously produce a collection type C, enumerator type E and element type T. A foreach statement of the form</p> </blockquote> <pre><code>foreach (V v in x) embedded-statement </code></pre> <blockquote> <p>is then expanded to: </p> </blockquote> <pre><code>{ E e = ((C)(x)).GetEnumerator(); try { V v; while (e.MoveNext()) { v = (V)(T)e.Current; embedded-statement } } finally { ... // Dispose e } } </code></pre> <p>The enumeration conversion itself is covered in section 6.2.2:</p> <blockquote> <p>The explicit enumeration conversions are:</p> </blockquote> <ul> <li>From sbyte, byte, short, ushort, int, uint, long, ulong, char, float, double, or decimal to any enum-type.</li> <li>From any enum-type to sbyte, byte, short, ushort, int, uint, long, ulong, char, float, double, or decimal.</li> <li>From any enum-type to any other enum-type.</li> </ul> <blockquote> <p>An explicit enumeration conversion between two types is processed by treating any participating enum-type as the underlying type of that enum-type, and then performing an implicit or explicit numeric conversion between the resulting types. For example, given an enum-type E with and underlying type of int, a conversion from E to byte is processed as an explicit numeric conversion (§6.2.1) from int to byte, and a conversion from byte to E is processed as an implicit numeric conversion (§6.1.2) from byte to int.</p> </blockquote>
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    1. POAre enums only named integers, types or neither of both?
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    1. USJon Skeet
    1. USJon Skeet
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    1. POAre enums only named integers, types or neither of both?
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    1. COYes very good answer. I realize now that explicit cast between enums of any type would not fail since they are practically an integers, and there was the root of the problem.
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      1. USAleksandar
 

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