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POGenericising one class to handle multiple types
 

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    <p>I have a series of about 30 lookup tables in my database schema, all with the same layout (and I would prefer to keep them as separate tables rather than one lookup table), and thus my Linq2SQL context has 30 entities for these lookup tables.</p> <p>I have a standard class that I would use for CRUD operations on each of these 30 entites, for example:</p> <pre><code>public class ExampleAttributes : IAttributeList { #region IAttributeList Members public bool AddItem(string Item, int SortOrder) { MyDataContext context = ContextHelper.GetContext(); ExampleAttribute a = new ExampleAttribute(); a.Name = Item; a.SortOrder = SortOrder; context.ExampleAttributes.InsertOnSubmit(a); try { context.SubmitChanges(); return true; } catch { return false; } } public bool DeleteItem(int Id) { MyDataContext context = ContextHelper.GetContext(); ExampleAttribute a = (from m in context.ExampleAttributes where m.Id == Id select m).FirstOrDefault(); if (a == null) return true; // Make sure nothing is using it int Count = (from m in context.Businesses where m.ExampleAttributeId == a.Id select m).Count(); if (Count &gt; 0) return false; // Delete the item context.ExampleAttributes.DeleteOnSubmit(a); try { context.SubmitChanges(); return true; } catch { return false; } } public bool UpdateItem(int Id, string Item, int SortOrder) { MyDataContext context = ContextHelper.GetContext(); ExampleAttribute a = (from m in context.ExampleAttributes where m.Id == Id select m).FirstOrDefault(); a.Name = Item; a.SortOrder = SortOrder; try { context.SubmitChanges(); return true; } catch { return false; } } public String GetItem(int Id) { MyDataContext context = ContextHelper.GetContext(); var Attribute = (from a in context.ExampleAttributes where a.Id == Id select a).FirstOrDefault(); return Attribute.Name; } public Dictionary&lt;int, string&gt; GetItems() { Dictionary&lt;int, string&gt; Attributes = new Dictionary&lt;int, string&gt;(); MyDataContext context = ContextHelper.GetContext(); context.ObjectTrackingEnabled = false; Attributes = (from o in context.ExampleAttributes orderby o.Name select new { o.Id, o.Name }).AsEnumerable().ToDictionary(k =&gt; k.Id, v =&gt; v.Name); return Attributes; } #endregion } </code></pre> <p>I could replicate this class 30 times with very minor changes for each lookup entity, but that seems messy somehow - so can this class be genericised so I can also pass it the type I want, and have it handle internally the type differences in the linq queries? That way, I have one class to make additions to, one class to bug fix et al - seems the way that it should be done.</p> <p><strong>UPDATE:</strong></p> <p>Andrews answer below gave me the option that I was really looking at while thinking about the question (passing the type in) but I need more clarification on how to genericise the linq queries. Can anyone clarify this?</p> <p>Cheers</p> <p>Moo</p>
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