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    <p>LINQ makes this pretty simple to do, by relying on the fact that the default value of any numeric type is zero, and they have appropriate equality methods:</p> <pre><code>private bool AtLeastOneBufferItemIsNonZero&lt;T&gt;(T[] items) { T zero = default(T); EqualityComparer&lt;T&gt; comparer = EqualityComparer&lt;T&gt;.Default; return items.Any(t =&gt; !comparer.Equals(t, zero)); } </code></pre> <p>Now that doesn't restrict it to numeric types, but it does avoid repetition. You can go further, by generalizing it to <code>IEnumerable&lt;T&gt;</code> and making it an extension method:</p> <pre><code>public static class Extensions { public static bool ContainsNonDefaultValue&lt;T&gt;(this IEnumerable&lt;T&gt; source) { if (source == null) { throw new ArgumentNullException("source"); } T zero = default(T); EqualityComparer&lt;T&gt; comparer = EqualityComparer&lt;T&gt;.Default; return items.Any(t =&gt; !comparer.Equals(t, zero)); } } </code></pre> <p>You <em>could</em> restrict this to value types by changing the constraint to</p> <pre><code>where T : struct </code></pre> <p>but that would be a bit pointless IMO. With the change to use <code>EqualityComparer&lt;T&gt;.Default</code>, you can <em>also</em> use the method to check whether any value in a reference type sequence is non-null.</p> <p>EDIT: As a side note, another way of look at it is to reverse the condition:</p> <pre><code>return !items.All(t =&gt; comparer.Equals(t, zero)); </code></pre> <p>It depends whether you're happier with the concept of "any of them is non-zero" or "they're not all zero" :)</p>
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    1. COBut that returns a value indicating whether at least one item *is* zero?
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      1. USFredrik Mörk
    2. CO@Fredrik: Doh, yes - fixing...
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    3. COBut shouldn't that then be named `AtLeastOneBufferItemIsZero`?
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      1. USJim Mischel
 

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