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    <p>This would require a sort (O(n <em>log</em> n)) but is very simple and flexible. Another advantage is being able to use it with LINQ to SQL:</p> <pre><code>var maxObject = list.OrderByDescending(item =&gt; item.Height).First(); </code></pre> <p>Note that this has the advantage of enumerating the <code>list</code> sequence just once. While it might not matter if <code>list</code> is a <code>List&lt;T&gt;</code> that doesn't change in the meantime, it could matter for arbitrary <code>IEnumerable&lt;T&gt;</code> objects. Nothing guarantees that the sequence doesn't change in different enumerations so methods that are doing it multiple times can be dangerous (and inefficient, depending on the nature of the sequence). However, it's still a less than ideal solution for large sequences. I suggest writing your own <code>MaxObject</code> extension manually if you have a large set of items to be able to do it in one pass without sorting and other stuff whatsoever (O(n)):</p> <pre><code>static class EnumerableExtensions { public static T MaxObject&lt;T,U&gt;(this IEnumerable&lt;T&gt; source, Func&lt;T,U&gt; selector) where U : IComparable&lt;U&gt; { if (source == null) throw new ArgumentNullException("source"); bool first = true; T maxObj = default(T); U maxKey = default(U); foreach (var item in source) { if (first) { maxObj = item; maxKey = selector(maxObj); first = false; } else { U currentKey = selector(item); if (currentKey.CompareTo(maxKey) &gt; 0) { maxKey = currentKey; maxObj = item; } } } if (first) throw new InvalidOperationException("Sequence is empty."); return maxObj; } } </code></pre> <p>and use it with:</p> <pre><code>var maxObject = list.MaxObject(item =&gt; item.Height); </code></pre>
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    1. POLINQ: How to perform .Max() on a property of all objects in a collection and return the object with maximum value
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    1. USMehrdad Afshari
    1. USMehrdad Afshari
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    1. CORats, didn't see this before I posted. That's basically what we do in MoreLINQ, except we iterate directly using GetEnumerator rather than having a "first" flag. I think it makes the code a bit simpler. We also allow use Comparer<U> and allow one to be passed in, rather than requiring U to implement IComparable, but that's a side issue.
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      1. USJon Skeet
    2. COThe last part is a lot of unnecessary complexity for a simple problem.
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      1. USKristoferA
    3. COThis is a solution for a more generic problem. Basically, you declare such an extension method to *abstract away* the complexity whenever you need it.
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      1. USMehrdad Afshari
 

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