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POUsing Entity Framework, how do I add a record to the mapping table in a Many to Many relationship
 

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    <p>I have the following tables (condensed for readability):</p> <h2>Call</h2> <p>ID CallerName CallerTime</p> <h2>Categories</h2> <p>ID CategoryName</p> <h2>CallCategories</h2> <p>CallID CategoryID</p> <p>When I modeled these in the Entity Framework the mapping talbe "CallCategories" was left out. I am stumped on how to get a record added to this table via the EF.</p> <p>I have gotten this far:</p> <pre><code>public void AddCategory(int callID, int categoryID) { using (var context = new CSMSEntities()) { try { //Get the Call var call = context.Calls.FirstOrDefault(x =&gt; x.callID == callID); //Create a new Category Category category = new Category(); category.categoryID = categoryID; //Add the Category to the Call call.Categories.Add(category); context.SaveChanges(); } catch (Exception ex) { throw ex; } } } </code></pre> <p>Do I use "Add" or "Attach". Also, it seems like I may be approaching this wrong. Should I actually be creating a new Category? It seems like that would create an actual record in the Category table, when I really want to just add a record to the many-to-many mapping table.</p> <p>I just can't seem to wrap my brain around some of this EF stuff. :-/</p> <p>Any help is MUCH appreciated!</p> <p>In response to gnome....</p> <p>I think you are onto something here. Although, wouldn't I call "Add" (or is it Attach)? Like:</p> <pre><code>//Get the Call var call = context.Calls.FirstOrDefault(x =&gt; x.callID == callID); //Find the Category and Add to the Call Category category = context.Categories.FirstOrDefault(c =&gt; c.categoryID == categoryID); call.Categories.Add(category); context.SaveChanges(); </code></pre>
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

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