wpf – 使用datacontract进行哈希表序列化时出现问题

XML serialization of hash table(C#3.0)

但我收到的错误是

不要求输入数据合同名称为“AllMyHashtable：http://schemas.datacontract.org/2004/07/WpfApplication3”的“WpfApplication3.MyHashtable”.将任何静态未知的类型添加到已知类型列表中 – 例如,通过使用KnownTypeAttribute属性或将它们添加到传递给DataContractSerializer的已知类型列表中.

我的计划如下

namespace WpfApplication3
{
    /// <summary>
    /// Interaction logic for Window1.xaml
    /// </summary>
    public partial class Window1 : Window
    {
        public Window1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender,RoutedEventArgs e)
        {
            MyHashtable ht = new MyHashtable();

            DateTime dt = DateTime.Now;
            for (int i = 0; i < 10; i++)
                ht.Add(dt.AddDays(i),i);
            SerializeToXmlAsFile(typeof(Hashtable),ht); 
        }

        private void SerializeToXmlAsFile(Type targetType,Object targetObject)
        {
            try
            {
                string fileName = @"C:output.xml";
                DataContractSerializer s = new DataContractSerializer(targetType);
                XmlWriterSettings settings = new XmlWriterSettings();
                settings.Indent = true;
                settings.IndentChars = ("    ");
                using (XmlWriter w = XmlWriter.Create(fileName,settings))
                {
                    s.WriteObject(w,targetObject);
                    w.Flush();
                }
            }
            catch (Exception ex) { throw ex; }
        }
    }

    [CollectionDataContract(Name = "AllMyHashtable",ItemName = "MyEntry",KeyName = "MyDate",ValueName = "MyValue")] 

    public class MyHashtable : Dictionary<DateTime,int> { }


}

What wrong is hapenning ..please help.

谢谢