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copied!<p>Your test is not accurate; in the <code>foreach</code> version, you're actually spinning up the enumerator and retrieving each value from the list (even though you aren't using it). In the <code>for</code> version, you aren't doing anything with the list at all, other than looking at its <code>Count</code> property. You're essentially testing the performance of an enumerator traversing a collection compared to incrementing an integer variable an equivalent number of times.</p> <p>To create parity, you'd need to declare a temporary variable and assign it in each iteration of the <code>for</code> loop.</p> <p>That being said, the answer to your question is <em>yes</em>. A copy of the value will be created with every assignment or <code>return</code> statement.</p> <h3>Performance</h3> <p>This pseudocode breakdown should explain why <code>foreach</code> is somewhat slower than using <code>for</code> in this particular instance:</p> <p><code>foreach</code>:</p> <pre><code>try { var en = test.GetEnumerator(); //creates a ListEnumerator T item; while(en.MoveNext()) // MoveNext increments the current index and returns // true if the new index is valid, or false if it's // beyond the end of the list. If it returns true, // it retrieves the value at that index and holds it // in an instance variable { item = en.Current; // Current retrieves the value of the current instance // variable } } finally { } </code></pre> <p><code>for</code>:</p> <pre><code>int index = -1; T item; while(++index < test.Count) { item = test[index]; } </code></pre> <p>As you can see, there's simply less code in the <code>for</code> implementation, and <code>foreach</code> has a layer of abstraction (the enumerator) on top of the <code>for</code>. I wrote the <code>for</code> using a <code>while</code> loop to show the two versions in a similar representation.</p> <h3>With all that said...</h3> <p>You're talking about a trivial difference in execution time. Use the loop that makes the code clearer and smaller, and in this circumstance that looks like <code>foreach</code>.</p>

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