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    <p>That might not be the easiest code to understand but I've tested it and it seems to work as intended.</p> <p>Let's setup some data.</p> <pre><code>var array = new [] { new { Sort = 1, Value = "foo1", }, new { Sort = 2, Value = "foo2", }, new { Sort = 3, Value = "foo3", }, new { Sort = 4, Value = "foo4", }, }; var oldSort = 1; var newSort = 3; </code></pre> <p>First, query is split into three parts depending on positions of old and new indexes, so we can handle each case separately.</p> <pre><code>var q = oldSort &gt; newSort ? array .Where(x =&gt; x.Sort &gt;= newSort &amp;&amp; x.Sort &lt; oldSort) .Select(x =&gt; new { Sort = x.Sort + 1, Value = x.Value }) .Union(array.Where(x =&gt; x.Sort &lt; newSort || x.Sort &gt; oldSort)) .Union(array.Where(x =&gt; x.Sort == oldSort) .Select(x =&gt; new { Sort = newSort, Value = x.Value })) : oldSort &lt; newSort ? array .Where(x =&gt; x.Sort &lt;= newSort &amp;&amp; x.Sort &gt; oldSort) .Select(x =&gt; new { Sort = x.Sort - 1, Value = x.Value }) .Union(array.Where(x =&gt; x.Sort &gt; newSort || x.Sort &lt; oldSort)) .Union(array.Where(x =&gt; x.Sort == oldSort) .Select(x =&gt; new { Sort = newSort, Value = x.Value })) : array; </code></pre> <p>Results for moving an item down (<code>oldSort = 1</code>, <code>newSort = 3</code>):</p> <pre><code>1 foo2 2 foo3 3 foo1 4 foo4 </code></pre> <p>Results for moving an item up (<code>oldSort = 4</code>, <code>newSort = 2</code>):</p> <pre><code>1 foo1 2 foo4 3 foo2 4 foo3 </code></pre> <p><strong>UPDATE</strong>: The query works by splitting a sequence into three parts</p> <ul> <li>Item with the old index becomes an item with the new index;</li> <li>Items between the old and new indexes are shifted either up or down;</li> <li>The rest keeps their indexes.</li> </ul> <p>The result is the union of the parts.</p> <p><strong>UPDATE 2</strong>: The query works for any number of items and the absence of loops is intentional.</p> <p><strong>UPDATE 3</strong>: Here's one way to make the query work with LINQ-to-Entities.</p> <pre><code>using (var context = new TestDBEntities()) { var array = context.TestTables; var q = oldSort &gt; newSort ? array .Where(x =&gt; x.Sort &gt;= newSort &amp;&amp; x.Sort &lt; oldSort) .Select(x =&gt; new { Sort = x.Sort + 1, Value = x.Value }) .Union(array.Where(x =&gt; x.Sort &lt; newSort || x.Sort &gt; oldSort) .Select(x =&gt; new { Sort = x.Sort, Value = x.Value })) .Union(array.Where(x =&gt; x.Sort == oldSort) .Select(x =&gt; new { Sort = newSort, Value = x.Value })) : oldSort &lt; newSort ? array .Where(x =&gt; x.Sort &lt;= newSort &amp;&amp; x.Sort &gt; oldSort) .Select(x =&gt; new { Sort = x.Sort - 1, Value = x.Value }) .Union(array.Where(x =&gt; x.Sort &gt; newSort || x.Sort &lt; oldSort) .Select(x =&gt; new { Sort = x.Sort, Value = x.Value })) .Union(array.Where(x =&gt; x.Sort == oldSort) .Select(x =&gt; new { Sort = newSort, Value = x.Value })) : array.Select(x =&gt; new { Sort = x.Sort, Value = x.Value }); } </code></pre> <p>The difference is that the types are now explicitly compatible. </p>
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    1. COThis is for only 3 items right? But what if there are 100? It should be more dynamic. And i think i'll need a loop for this to get the job done.
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    2. CO@Yustme The query doesn't depend on number of items. And the point of using LINQ is to avoid loops. Anyway, please test and let us know.
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    3. COWhile this might work indeed (I didn't test it) and the OP asked for a LINQ solution, I think that LINQ should not be used for this. LINQ should simplify things, not make them more complicated.
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