/// <summary>
/// 从指定的URL加载XML文件，并赋值到<see cref="IXmlSavable"/>实例中。
/// </summary>
/// <param name="savable">实例。</param>
/// <param name="filename">文件URL。</param>
public static void Load(this IXmlSavable savable, string filename)
{
XmlDocument doc = new XmlDocument();
doc.Load(filename);
XmlElement target;
if (doc.DocumentElement.Name == savable.Name)
{
target = doc.DocumentElement;
}
else
{
target = doc.DocumentElement.GetElement(savable.Name) as XmlElement;
}
if (target != null)
{
savable.FromXmlElement(target);
}
}
