■No35578に返信(夏風さんの記事)
数年前、同じようなこと考えて色々作り込んだ後、ジェネリックの部分だけ
あれば事足りるんじゃないかという結論になったことがある。。。
    class MainClass
    {
        public static void Main()
        {
            const string strBasePath = @"C:\test\";
            string strForm1XML = Path.Combine(strBasePath, @"Form1Setting.xml");
            string strForm2XML = Path.Combine(strBasePath, @"Form2Setting.xml");

            clsGenericsTest<clsForm1Setting> obj1 = new clsGenericsTest<clsForm1Setting>(strForm1XML);
            clsForm1Setting objSaveItem1 = new clsForm1Setting();
            objSaveItem1.TimeStamp = DateTime.Now;
            obj1.SaveFile(objSaveItem1);

            clsGenericsTest<clsForm2Setting> obj2 = new clsGenericsTest<clsForm2Setting>(strForm2XML);
            clsForm2Setting objSaveItem2 = new clsForm2Setting();
            objSaveItem2.TimeStamp = DateTime.Now.AddDays(10);
            obj2.SaveFile(objSaveItem2);
        }
    }
    public class clsForm1Setting
    {
        public DateTime TimeStamp;
    }
    public class clsForm2Setting
    {
        public DateTime TimeStamp;
    }
    public class clsGenericsTest<T> where T : class, new()
    {
        private string _filePath;
        private clsGenericsTest() { }
        public clsGenericsTest(string FilePath) { _filePath = FilePath; }
        public void SaveFile(T item)
        {
            XmlSerializer serializer1 = new XmlSerializer(typeof(T));
            StreamWriter sw = new StreamWriter(_filePath, false, Encoding.GetEncoding("Shift_JIS"));
            serializer1.Serialize(sw, item);
            sw.Close();
        }
        public T ReadFile()
        {
            XmlSerializer serializer = new XmlSerializer(typeof(T));
            StreamReader sr = new StreamReader(_filePath, Encoding.GetEncoding("Shift_JIS"));
            T obj = (T)serializer.Deserialize(sr);
            sr.Close();

            return obj;
        }
    }