C#创建文件关联

public class FileAssociations
    {
        // needed so that Explorer windows get refreshed after the registry is updated
        [System.Runtime.InteropServices.DllImport("Shell32.dll")]
        private static extern int SHChangeNotify(int eventId, int flags, IntPtr item1, IntPtr item2);

        private const int SHCNE_ASSOCCHANGED = 0x8000000;
        private const int SHCNF_FLUSH = 0x1000;

        public static void EnsureAssociationsSet()
        {
            var filePath = Process.GetCurrentProcess().MainModule.FileName;
            EnsureAssociationsSet(
                new FileAssociation
                {
                    Extension = ".ucs",
                    ProgId = "UCS_Editor_File",
                    FileTypeDescription = "UCS File",
                    ExecutableFilePath = filePath
                });
        }

        public static void EnsureAssociationsSet(params FileAssociation[] associations)
        {
            bool madeChanges = false;
            foreach (var association in associations)
            {
                madeChanges |= SetAssociation(
                    association.Extension,
                    association.ProgId,
                    association.FileTypeDescription,
                    association.ExecutableFilePath,association.ExecutableIconPath);
            }

            if (madeChanges)
            {
                SHChangeNotify(SHCNE_ASSOCCHANGED, SHCNF_FLUSH, IntPtr.Zero, IntPtr.Zero);
            }
        }

        public static bool SetAssociation(string extension, string progId, string fileTypeDescription,
            string applicationFilePath,string applicationIconPath)
        {
            bool madeChanges = false;
            madeChanges |= SetKeyDefaultValue(@"Software\Classes\" + extension, progId);
            madeChanges |= SetKeyDefaultValue(@"Software\Classes\" + progId, fileTypeDescription);
            madeChanges |= SetKeyDefaultValue($@"Software\Classes\{progId}\shell\open\command",
                "\"" + applicationFilePath + "\" \"%1\"");
            madeChanges |= SetKeyDefaultValue($@"Software\Classes\{progId}\DefaultIcon", applicationIconPath);
            return madeChanges;
        }

        private static bool SetKeyDefaultValue(string keyPath, string value)
        {
            using (var key = Registry.CurrentUser.CreateSubKey(keyPath))
            {
                if (key.GetValue(null) as string != value)
                {
                    key.SetValue(null, value);
                    return true;
                }
            }

            return false;
        }
    }

public class FileAssociation
    {
        public string Extension { get; set; }
        public string ProgId { get; set; }
        public string FileTypeDescription { get; set; }
        public string ExecutableFilePath { get; set; }
        public string ExecutableIconPath { get; set; }
    }