CommonSettings.cs

using System;
using Microsoft.Win32;

namespace Common
{
        public class CommonSettings     {
                private RegistryKey regKey;

                public CommonSettings() {
                        regKey = Registry.CurrentUser.OpenSubKey("Software\\University of Cambridge\\GPRSWeb\\Common", true);
                }

                private string cacheLocation = null; 
                public string CacheLocation {
                        get {
                                if (cacheLocation == null) {
                                        cacheLocation = (string)regKey.GetValue("CacheLocation");
                                } // it may return null if we can't find it, so do 2nd check
                                if (cacheLocation != null) {
                                        return cacheLocation;
                                } else {
                                        throw new ApplicationException("Unable to fetch Cache Location: none set in registry");
                                }
                        }
                }

                private string cacheFileExtension = null;
                public string CacheFileExtension {
                        get {
                                if (cacheFileExtension == null) {
                                        cacheFileExtension = (string)regKey.GetValue("CacheFileExtension");
                                } // it may return null if we can't find it, so do 2nd check
                                if (cacheFileExtension != null) {
                                        return cacheFileExtension;
                                } else {
                                        throw new ApplicationException("Unable to fetch Cache File Extension: none set in registry");
                                }
                        }
                }
        }
}

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