Dynamic/Transparent Proxy using DynamicProxy.NET

using System;

namespace DynamicProxyTutorial {
	/// <summary>
	/// Simple factory (also a pattern from GoF) 
	/// that encapsulates the creation of proxies for the IFileViewer interface.
	/// There's no requirement for encapsulting this in a factory,
	/// it's just a good idea to keep this seperate from the usage of the fileviewer
	/// </summary>
	public class FileViewerProxyFactory {

		/// <summary>
		/// Keep the constructor private, to prevent instantiations.
		/// </summary>
		private FileViewerProxyFactory() {
		}

		/// <summary>
		/// Static method to create new proxy instances
		/// </summary>
		/// <param name="filePath">The path to the file we want to view</param>
		/// <param name="allowedUserID">The userid for the user that's allowed to view the file</param>
		/// <param name="useDynamicProxyNET">If true we use DynamicProxy.NET to create a proxy at runtime, else
		/// we use the handwritten FileViewerProxy class</param>
		/// <returns>A new File Viewer proxy instance</returns>
		public static IFileViewer createProxy(string filePath, string allowedUserID, bool useDynamicProxyNET) {
			if (useDynamicProxyNET) {
				return new DynamicFileViewerProxy(filePath, allowedUserID).Proxy;
			} else {
				return new FileViewerProxy(filePath, allowedUserID);
			}
		}
	}
}