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POHierarchical Database Driven Menu in MVC
 

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    <p>I use the code below as an HTMLHelper which gets data from the database and loops over it to display a menu. This is fairly straightforward as you can see however, what if you have a database table using the adjacent model of hierarchies eg/ID, ParentID, OrderID. Easy to see whats going on but recursion is needed to get this data out properly. Is writing a C# recursive function acceptable? If so can someone help me with that? The expected output is something similar to this..</p> <pre><code>&lt;ul&gt; &lt;li&gt;Item1 &lt;ul&gt; &lt;li&gt;SubItem1&lt;/li&gt; &lt;/ul&gt; &lt;/li&gt; &lt;/ul&gt; </code></pre> <p>SQL 2008 has a Hierarchy datatype now so I am not sure if this will help things? </p> <p>I would also like some way of enabling users to decide what goes in a menu for example, a list of items that can go in the menu and then choosing these items and their positions in the hierarchy. Once a saved button is pressed it will store this heirarchy in the database.</p> <p>Am I asking too much, I'm sure this must be quite a common scenario?</p> <p>Here is my HTMLHelper code if anyone wants to use it...</p> <pre><code> public static string Menu(this HtmlHelper helper, int MenuCat) { string menuHTML = "&lt;ul id=\"menu\"&gt;"; var route = helper.ViewContext.RequestContext.RouteData; string currentPageName = route.GetRequiredString("id"); DB db = DB.CreateDB(); //var result = from p in db.WebPages where p.CategoryID == 9 select p; var result = from p in db.WebPages select p; foreach (var item in result) { if (item.Name == currentPageName) { menuHTML += "\n\t&lt;li&gt;" + helper.ActionLink(item.Name, "Details", "Dinner", new { id = item.ID }, new { @class = "selected" }) + "&lt;/li&gt;"; } else { menuHTML += "\n\t&lt;li&gt;" + helper.ActionLink(item.Name, "Details", "Dinner", new { id = item.ID }, null) + "&lt;/li&gt;"; } } menuHTML += "\n&lt;/ul&gt;\n"; return menuHTML; } </code></pre>
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