c# - 使用 pocos 以声明方式定义 xml 序列化

Question

通常在 C# 中，Xml 类型都标有属性来定义它们的获取方式 序列化:

/// <remarks/>
[System.Xml.Serialization.XmlTypeAttribute(Namespace=
"urn:xmlns:25hoursaday-com:my-bookshelf")]
public class bookType {

    /// <remarks/>
    public string title;

    /// <remarks/>
    public string author;

   /// <remarks/>
   [System.Xml.Serialization.XmlElementAttribute("publication-date", 
DataType="date")]      
    public System.DateTime publicationdate;

    /// <remarks/>
    [System.Xml.Serialization.XmlAttributeAttribute()]
    public string publisher;

    /// <remarks/>
    [System.Xml.Serialization.XmlAttributeAttribute("on-loan")]
    public string onloan;
}

现在说到我喜欢在没有这些属性的情况下使用 POCOS，我可能会重新使用这些属性来进行 OR-Mapping，例如NHibernate，那么在不改变要序列化的类型的情况下定义序列化方式会很好。

问题是:是否有一种方法可以 declerativeley 定义类型序列化的方式，例如:映射 xml 文件。

Answer 1

是的:

    XmlAttributeOverrides attribs = new XmlAttributeOverrides();
    attribs.Add(typeof(bookType), new XmlAttributes
    {
        XmlType = new XmlTypeAttribute { Namespace = "urn:xmlns:25hoursaday-com:my-bookshelf" },
    });
    attribs.Add(typeof(bookType), "publicationdate", new XmlAttributes
    {
        XmlElements = { new XmlElementAttribute("publication-date") { DataType = "date" } }
    });
    attribs.Add(typeof(bookType), "publisher", new XmlAttributes
    {
        XmlAttribute = new XmlAttributeAttribute()
    });
    attribs.Add(typeof(bookType), "onloan", new XmlAttributes
    {
        XmlAttribute = new XmlAttributeAttribute("on-loan")
    });

然后序列化为:

    XmlSerializer s = new XmlSerializer(typeof(bookType), attribs);
    var obj = new bookType { title = "a", author = "b",
        publicationdate = DateTime.Now, publisher = "c", onloan = "d"};
    s.Serialize(Console.Out, obj);

然而

我怎么警告都不为过；您必须缓存并重新使用以这种方式创建的XmlSerializer 对象，因为每个对象都会创建一个无法卸载 的动态序列化程序集。如果您不缓存和重用，您将淹没内存。