/// 
    /// 通用的单例制作器    /// 
    /// 
        public class UniversalSingletonGeneator
    
      where T : Form,new()    {        private static T t = null;        public static T CreateSingleton()        {            if (t == null || t.IsDisposed)            {                t = new T();            }            t.WindowState = FormWindowState.Normal;            t.Activate();            return t;        }    }   // 测试代码    var pFrm = UniversalSingletonGeneator
     
      .CreateSingleton();    pFrm.Show();