Restructuring the project, first steps.

src/GreenshotPlugin/Core/RegistryKeyExtensions.cs

@@ -0,0 +1,88 @@
+/*
+ * Greenshot - a free and open source screenshot tool
+ * Copyright (C) 2007-2021 Thomas Braun, Jens Klingen, Robin Krom
+ * 
+ * For more information see: http://getgreenshot.org/
+ * The Greenshot project is hosted on GitHub https://github.com/greenshot/greenshot
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 1 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+using System;
+using Microsoft.Win32;
+
+namespace GreenshotPlugin.Core
+{
+    /// <summary>
+    /// A helper class for accessing the registry
+    /// </summary>
+    public static class RegistryKeyExtensions
+    {
+        /// <summary>
+        /// Retrieve a registry value
+        /// </summary>
+        /// <param name="registryHive">RegistryHive like RegistryHive.LocalMachine</param>
+        /// <param name="keyName">string with the name of the key</param>
+        /// <param name="value">string with the name of the value below the key, null will retrieve the default</param>
+        /// <param name="defaultValue">string with the default value to return</param>
+        /// <returns>string with the value</returns>
+        public static string ReadKey64Or32(this RegistryHive registryHive, string keyName, string value = null, string defaultValue = null)
+        {
+            string result = null;
+            value ??= string.Empty;
+
+            using var registryKey32 = RegistryKey.OpenBaseKey(registryHive, RegistryView.Registry32);
+            // Logic for 32-bit Windows is just reading the key
+            if (!Environment.Is64BitOperatingSystem)
+            {
+                using var key = registryKey32.OpenSubKey($@"SOFTWARE\{keyName}", false);
+
+                if (key != null)
+                {
+                    result = (string)key.GetValue(value);
+                }
+                if (string.IsNullOrEmpty(result))
+                {
+                    result = defaultValue;
+                }
+                return result;
+            }
+            using var registryKey64 = RegistryKey.OpenBaseKey(registryHive, RegistryView.Registry64);
+            // Logic for 64 bit Windows, is trying the key which is 64 bit
+            using (var key = registryKey64.OpenSubKey($@"SOFTWARE\{keyName}", false))
+            {
+                if (key != null)
+                {
+                    result = (string)key.GetValue(value);
+                }
+                if (!string.IsNullOrEmpty(result)) return result;
+            }
+
+            // if there is no value use the wow6432node key which is 32 bit
+            using (var key = registryKey32.OpenSubKey($@"SOFTWARE\{keyName}", false))
+            {
+                if (key != null)
+                {
+                    result = (string)key.GetValue(value);
+                }
+            }
+
+            if (string.IsNullOrEmpty(result))
+            {
+                result = defaultValue;
+            }
+            return result;
+        }
+    }
+}