class Program

    {

        static void Main(string[] args)

        {

            UserSearchRequest model = new UserSearchRequest()

            {

                Name = "'1'=0",

                Age =

            };

            Type type = model.GetType();

            //var ps = type.GetProperties();

            var ps = type.GetProperties().Where(u=>u.PropertyType.FullName =="System.String").ToList();

            foreach (var p in ps)

            {

                Console.WriteLine("PropertyName:{0},Value:{1}",p.Name,p.GetValue(model,null).ToString());

                p.SetValue(model, "",null);

                Console.WriteLine("PropertyName:{0},Value:{1}", p.Name, p.GetValue(model, null).ToString());

            }

            Console.ReadLine();

        }

    }

    public class UserSearchRequest

    {

        public string Name { set; get; }

        public int Age { set; get; }

    }