给定System.Type T,反序列化List <t> </t>

时间:2010-11-08 20:46:59

标签: c# asp.net xml-serialization xml-deserialization generic-list

我有许多我想要序列化和反序列化的类。我正在尝试创建一个函数,给定一个类型(“用户”,“管理员”,“文章”等)将使用这些项的列表反序列化文件。例如:

/* I want to be able to do this */
List<Article> allArticles = GetAllItems(typeof(Article));

我无法弄清楚如何实现上述目标,但我设法让这个工作:

/* BAD: clumsy method - have to pass a (typeof(List<Article>)) 
    instead of typeof(Article)  */
List<Article> allArticles = (List<Article>)GetAllItems(typeof(List<Article>));

/* Then later in the code... */
public static IList GetAllItems(System.Type T)
{

    XmlSerializer deSerializer = new XmlSerializer(T);

    TextReader tr = new StreamReader(GetPathBasedOnType(T));
    IList items = (IList) deSerializer.Deserialize(tr);
    tr.Close();

    return items;
}

问题是我必须传递“丑陋”typeof(List<Article>)而不是“漂亮”typeof(Article)

当我尝试这个时:

List<User> people = (List<User>)MasterContactLists.GetAllItems(typeof(User));

/* Followed by later in the code...*/
public static IList GetAllItems(System.Type T)
{
    XmlSerializer deSerializer = new XmlSerializer(typeof(List<T>));

    TextReader tr = new StreamReader(GetPathBasedOnType(T));
    IList items = (IList)deSerializer.Deserialize(tr);
    tr.Close();

    return items;
}

...我收到错误

/*Error 3 
The type or namespace name 'T' could not be found 
(are you missing a using directive or an assembly reference?)
on this line: ... = new XmlSerializer(typeof(List<T>)); */

问题:如何修复我的GetAllItems()以便能够像这样调用函数并让它返回一个列表:

List<Article> allArticles = GetAllItems(typeof(Article));

谢谢!

1 个答案:

答案 0 :(得分:3)

你差不多......你需要声明一个通用的方法:

public static IList<T> GetAllItems<T>()
{
    XmlSerializer deSerializer = new XmlSerializer(typeof(List<T>));

    using(TextReader tr = new StreamReader(GetPathBasedOnType(typeof(T))))
    {
        IList<T> items = (IList<T>)deSerializer.Deserialize(tr);
    }

    return items;
}