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POLINQ query with group by and ascending ordering not working
 

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  1. POLINQ query with group by and ascending ordering not working
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    <p>I have a class Ingredients which has a property <code>Items</code> of the type <code>List&lt;Ingredient&gt;</code>.<br> In one of my pages I am using a GridView to display all the ingredients, grouped by first letter:</p> <pre class="lang-xml prettyprint-override"><code>&lt;Page.Resources&gt; &lt;CollectionViewSource x:Name="IngredientsViewSource" IsSourceGrouped="True" ItemsPath="Items"/&gt; &lt;/Page.Resources&gt; </code></pre> <p>when the page is loaded, the CollectionViewSource's Source property is set like this:</p> <pre><code>this.IngredientsViewSource.Source = CurrentData.Ingredients.GroupedItems; </code></pre> <p><code>GroupedItems</code> is a property of the Ingredients class, which takes the property <code>Items</code> and orders and groups everything in order to be ready to use:</p> <pre class="lang-cs prettyprint-override"><code>public object GroupedItems { get { if (this.Items != null) { return from IngredientIteration in this.Items //orderby IngredientIteration.Name ascending group IngredientIteration by IngredientIteration.FirstLetter into IngredientGroup //orderby IngredientGroup.Key ascending select new { FirstLetter = IngredientGroup.Key, Items = IngredientGroup }; } else { return null; } } private set { } } </code></pre> <p>this is working quite well. Now I would like to sort the result, because now the first letters' order is all messed up. However, when I remove the comment marks in front of the two <code>orderby</code> clauses, it get's totally weird. Leaving the orderby clauses like it is now results in correctly ordered groups, but only the first item per group is showed.<br> When I change ascending to descending, though, everything works as expected: groups are sorted descending, all items are shown, and the items are sorted descending inside each group. </p> <p>This makes no sense to me, why is descending working but ascending not? Am I missing something here?</p>
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    1. USKjartan
    1. USDavide De Santis
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    1. COit looks to me that your `GroupedItems` would have the `Items` as an `IGrouping<...>`, I doubt that's not what you want. What's the actual data structure you want for each entry in `GroupedItems`?
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      1. POLINQ query with group by and ascending ordering not working
      1. USKing King
    2. COI'd like to have a collection of these anonymous objects with each a string `FirstLetter` and a `List<Ingredient>` `Items`.
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      1. POLINQ query with group by and ascending ordering not working
      1. USDavide De Santis
 

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