[AttributeUsageAttribute(AttributeTargets.All)] 
    public sealed class TypeConverterAttribute : Attribute

 [TypeConverter(typeof(LongitudeTypeConverter))]
    public class Longitude
    {}

class Test
    {
        public static void Main(string[] args)
        {
            //将Longitude类转换到string类型
            Longitude longitude = new Longitude(10,11,12,LongitudeDirection.East);
            LongitudeTypeConverter converter = new LongitudeTypeConverter();

            string strLongitude="";
            if (converter.CanConvertTo(typeof(string)))
            {
                //Longitude 类没有附件TypeconverterAttribute时
                strLongitude = (string)converter.ConvertTo(longitude, typeof(string));
                //Longitude 类附件了TypeconverterAttribute时
                strLongitude = (string)TypeDescriptor.GetConverter(typeof(Longitude)).ConvertTo(longitude, typeof(string));
            }
            System.Console.WriteLine(strLongitude);

            //将string还原回Longitude类
            Longitude longitude1 = new Longitude();
            if (converter.CanConvertFrom(typeof(string)))
            {
                //Longitude 类没有附件TypeconverterAttribute时
                longitude1 = (Longitude)converter.ConvertFrom(strLongitude);
                //Longitude 类附件了TypeconverterAttribute时
                longitude1 = (Longitude)TypeDescriptor.GetConverter(typeof(Longitude)).ConvertFrom(strLongitude);
            }
            System.Console.WriteLine(longitude1.Degrees);
            System.Console.WriteLine(longitude1.Direction);
            System.Console.WriteLine(longitude1.Minutes);
            System.Console.WriteLine(longitude1.Seconds);

        }
    }

 Type type = typeof(Longitude);
            //AttributeTargs包括method实体
            CustomTypeConverterAttribute customTypeConverterAttribute;

            foreach (Attribute att in type.GetCustomAttributes(typeof(OtherTypeConverter), true))
            {
                System.Console.WriteLine("OtherTypeConverter 的属性Property" + customTypeConverterAttribute.Property1);
            }

            foreach (MethodInfo method in type.GetMethods())
            {
                foreach (Attribute att in method.GetCustomAttributes(true))
                {
                    customTypeConverterAttribute = att as CustomTypeConverterAttribute;
                    if (null != customTypeConverterAttribute)
                    {
                        System.Console.WriteLine("类的方法是：" + method.Name + " 该方法的附加Attribute是：" + customTypeConverterAttribute.ToString());
                    }
                }
            }

 [Bindable(true)]
        [Category("Appearance")]
        [DefaultValue(typeof(GPSLocation), "")]
        [DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]
        [PersistenceMode(PersistenceMode.InnerProperty)]
        public GPSLocation Location
        {
            get
            {
                // if no instance created yet do so
                if (_Location == null)
                    _Location = new GPSLocation();

                return _Location;
            }
        }

<ui:LocationControl ID="LocationControl1" runat="server" 
        Location-GPSLatitude="12N1'2"" Location-GPSLongitude="24W3'4"">
</ui:LocationControl>

<ui:LocationControl ID="LocationControl1" runat="server">
   <Location GPSLatitude="12N1'3"" GPSLongitude="24W3'4"" />
</ui:LocationControl>