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POComparer is not getting called when Sorting an IList
 

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  1. POComparer is not getting called when Sorting an IList
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    <p>I have a really annoying error whereby my comparer.Compare(x, y) is not getting called. I have an IList that is returning a bunch of entities from the database and then I'm sorting a list of entities inside each entity returned from the database.</p> <p>ie: in this example each household has many accounts, and i want to sort the sub-list by properties on the accounts entities.</p> <p>My calling logic is as follow:</p> <pre><code> List&lt;Household&gt; households = query.ToList(); households.Sort(new HouseholdComparer()); return households; </code></pre> <p>and my comparer looks like this:</p> <pre><code>public class HouseholdComparer : IComparer&lt;Household&gt; { public int Compare(Household x, Household y) { foreach (Account xAccount in x.Accounts) { foreach (Account yAccount in y.Accounts) { if (xAccount.StartDate == yAccount.StartDate) { if ((xAccount.RevenueT12.HasValue &amp;&amp; yAccount.RevenueT12.HasValue) &amp;&amp; (xAccount.RevenueT12.Value == yAccount.RevenueT12.Value)) { if ((xAccount.AUAAnnual.HasValue &amp;&amp; yAccount.AUAAnnual.HasValue) &amp;&amp; (xAccount.AUAAnnual.Value == yAccount.AUAAnnual.Value)) return 0; // all same whatever result if (!xAccount.AUAAnnual.HasValue || !yAccount.AUAAnnual.HasValue) return 0; if (xAccount.AUAAnnual.Value &gt; yAccount.AUAAnnual.Value) return 1; if (xAccount.AUAAnnual.Value &lt; yAccount.AUAAnnual.Value) return -1; } else { if (!xAccount.RevenueT12.HasValue || !yAccount.RevenueT12.HasValue) return 0; if (xAccount.RevenueT12.Value &gt; yAccount.RevenueT12.Value) return 1; if (xAccount.RevenueT12.Value &lt; yAccount.RevenueT12.Value) return -1; } } else { if (x.StartDate &gt; y.StartDate) return 1; if (x.StartDate &lt; y.StartDate) return -1; } } } return 0; // it shouldn't get here } </code></pre> <p>When I run the debugger I get a hit in the constructor but nothing in the compare method, can anyone help?????</p>
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    1. PO
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      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. This table or related slice is empty.
    1. USJoshy
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      1. LTLinked
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
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      1. PTAnswer
    2. PO
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      1. PTAnswer
    3. PO
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    1. VO
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      1. POComparer is not getting called when Sorting an IList
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
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      1. POComparer is not getting called when Sorting an IList
      1. This table or related slice is empty.
      1. VTUpMod
    1. COI don't see any calls to Compare(). Did you overload the comparison operators?
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      1. POComparer is not getting called when Sorting an IList
      1. USPaddyd
    2. CODid you check whether the list is empty or contains just one element? The `Compare` method wouldn't be called for those cases.
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      1. POComparer is not getting called when Sorting an IList
      1. USDouglas
    3. COThis would be much easier to diagnose with a short but *complete* example demonstrating the problem. If the list is empty or only has a single element, it doesn't need to call the comparer.
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      1. POComparer is not getting called when Sorting an IList
      1. USJon Skeet
 

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