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POEntity Framework - Include in sub query? - Part 2
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  1. POEntity Framework - Include in sub query? - Part 2
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    copied!<p>I'm not sure if this is the right thing to do, I'm sure someone will tell me if it's not.</p> <p>I asked a question (<a href="https://stackoverflow.com/questions/1662760/entity-framework-include-in-sub-query">Entity Framework - Include in sub query?</a>) earlier this evening, which was answered very well and has solved my problem. But, I think there could be a better way, so I'm going to re-ask the question, but slightly differently.</p> <p>Let's say I have 3 tables:</p> <p>Restaurant 1.....M MenuCategory 1.....M MenuItem I have a L2E query that looks something like this:</p> <p>Restaurant = context.Restaurant .Include(r => r.MenuCategory) .FirstOrDefault(r => r.RestaurantId == resaurantId); Which works to some extent, but it only pre-loads the menu categories.</p> <p>What I really want to be able to do is something like:</p> <pre><code>Restaurant = context.Restaurant .Include(r =&gt; r.MenuCategory) .Include(r =&gt; r.MenuCategory.MenuItems) .FirstOrDefault(r =&gt; r.RestaurantId == resaurantId); </code></pre> <p>But clearly this isn't available as r.MenuCategory is an enumerable</p> <p>...the work around is to use the standard notation:</p> <pre><code>context.Restaurant.Include("MenuCategory.MenuItems"); </code></pre> <p>...but this is not strongly typed. This question is about finding a <strong>strongly typed</strong> answer</p> <p>This is the current extension method:</p> <pre><code>public static ObjectQuery&lt;T&gt; Include&lt;T&gt;(this ObjectQuery&lt;T&gt; query, Expression&lt;Func&lt;T, object&gt;&gt; path) { // Retrieve member path: List&lt;PropertyInfo&gt; members = new List&lt;PropertyInfo&gt;(); EntityFrameworkHelper.CollectRelationalMembers(path, members); // Build string path: StringBuilder sb = new StringBuilder(); string separator = ""; foreach (MemberInfo member in members) { sb.Append(separator); sb.Append(member.Name); separator = "."; } // Apply Include: return query.Include(sb.ToString()); } </code></pre> <p>How could this be adapted to allow a strongly typed form of:</p> <pre><code>context.Restaurant.Include("MenuCategory.MenuItems"); </code></pre>
 

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