public override String ToString()
    {
         Type objType = this.GetType();
         PropertyInfo[] propertyInfoList = objType.GetProperties();
         StringBuilder result = new StringBuilder();
         foreach (PropertyInfo propertyInfo in propertyInfoList)
             result.AppendFormat("{0}:{1},", propertyInfo.Name, propertyInfo.GetValue(this));
          
          return "{" + result.ToString() + "}";
     }