泛型方法中实例化一个有参数的泛型实例

 public static T GetInstance(DataRow dr)
        {
            var ctors = typeof(T).GetConstructors(
                  BindingFlags.Instance
                  | BindingFlags.NonPublic
                  | BindingFlags.Public);
            if (ctors.Count() != 1)
                throw new InvalidOperationException(String.Format("Type {0} must have exactly one constructor.", typeof(T)));
            var ctor = ctors.SingleOrDefault(c => c.IsPrivate);
            if (ctor == null)
                throw new InvalidOperationException(String.Format("The constructor for {0} must be private.", typeof(T)));
            return (T)ctor.Invoke(new object[] { dr });
        } public static T GetInstance(DataRow dr)
        {
            var ctors = typeof(T).GetConstructors(
                  BindingFlags.Instance
                  | BindingFlags.NonPublic
                  | BindingFlags.Public);
            if (ctors.Count() != 1)
                throw new InvalidOperationException(String.Format("Type {0} must have exactly one constructor.", typeof(T)));
            var ctor = ctors.SingleOrDefault(c => c.IsPrivate);
            if (ctor == null)
                throw new InvalidOperationException(String.Format("The constructor for {0} must be private.", typeof(T)));
            return (T)ctor.Invoke(new object[] { dr });
        }