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copied!<p>There are a few ways you could go about improving your current design. I don't agree that the solution I am about to present to you is the ideal solution, but given that you have already identified that you would like to use an <code>enum</code> I think you will be content with this solution. </p> <p>What you can do is define an <code>enum</code> marked with the <code>[Flags]</code> attribute. Assign to each flag in the enum a value that is a power of two. If you want to combine options to create a single option use <a href="http://msdn.microsoft.com/en-gb/library/kxszd0kx%28v=vs.71%29.aspx" rel="nofollow">bitwise or</a> just like I did with the flag named "All" in the proceeding sample: </p> <pre><code>[Flags] public enum GetItemOptions { Read = 0x1, Unread = 0x2, All = 0x1 | 0x2, SortByOldest = 0x4, SortByLatest = 0x8 } </code></pre> <p>From your code sample, the first call will now look like this: </p> <pre><code>GetItemsBasedOn(GetItemOptions.Unread | GetItemOptions.SortByLatest); </code></pre> <p>And the second will look like this: </p> <pre><code>GetItemsBasedOn(GetItemOptions.All); </code></pre> <p>In order to enable this design you will need to adjust your <code>GetItemsBasedOn</code> method signature so that it specifies an argument of the <code>GetItemOptions</code> enum type. Below is an example of how you can handle different settings. </p> <pre><code>public static void GetItemsBasedOn(GetItemOptions getItemOption) { if (getItemOption.HasFlag(GetItemOptions.SortByOldest) && getItemOption.HasFlag(GetItemOptions.SortByLatest)) throw new ArgumentException("I can't sort by both..."); if (getItemOption.HasFlag(GetItemOptions.Read)) { Console.WriteLine("READ"); } if (getItemOption.HasFlag(GetItemOptions.Unread)) { Console.WriteLine("UNREAD"); } if (getItemOption.HasFlag(GetItemOptions.SortByOldest)) { Console.WriteLine("SORT BY OLDEST"); } else if (getItemOption.HasFlag(GetItemOptions.SortByLatest)) { Console.WriteLine("SORT BY NLATEST"); } } </code></pre> <p>I don't think you know much about bit-wise operations, and for that reason I simplified the code sample as much as possible by utilizing the <code>Enum.HasFlag</code> method which simply checks if the given <code>GetItemOptions</code> enum has a flag specified. </p> <p>You may have bared witness to this pattern before when using <a href="http://msdn.microsoft.com/en-us/library/system.text.regularexpressions.regexoptions.aspx" rel="nofollow"><code>RegexOptions Enumeration</code></a> or <a href="http://msdn.microsoft.com/en-gb/library/system.windows.forms.controlstyles.aspx" rel="nofollow"><code>ControlStyles Enumeration</code></a></p> <h2>Update</h2> <p>I would suggest that you create an <code>enum</code> for each parameter and define a class like this:</p> <pre><code>public class PocketDataRequest { public State? State { get; set; } public Favourite? Favourite { get; set; } public ContentType? ContentType { get; set; } public Sort? Sort { get; set; } public DetailType? DetailType { get; set; } public Dictionary<string, string> ToPostData() { return GetType().GetProperties() .Where(p => p.GetValue(this, null) != null) .ToDictionary(p => p.Name, p => p.GetValue(this, null).ToString()); } } </code></pre> <p>This would leverage the following syntax: </p> <pre><code>PocketDataRequest pocketDataRequest = new PocketDataRequest(); pocketDataRequest.State = State.Unread; pocketDataRequest.Sort = Sort.Newest; GetItemsBasedOn(pocketDataRequest.ToPostData()); </code></pre> <p>In my implementations <code>ToPostData</code> method, I use LINQ and Reflection, that is just because I am lazy. You need to manually evaluate each <code>enum</code> value, especially if you want to change the <code>enum</code> names to something more appropriate. Also, my code will fail if you try and pass the parameter titled <code>favorite</code>. This is because <code>favorite</code> takes either the number "0" or "1". This is not a big problem because what you can do it define the <code>enum</code> like this: </p> <pre><code>public enum Favourite { UnfavouritedItems = 0, FavouritedItems = 1 } </code></pre> <p>and then simply cast the value <code>(Int32)</code> and add that value to the <code>Dictionary<string, string></code> or <code>NameValueCollection</code>.</p>

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