将XDocument / Elements转换为C＃类对象

Question

我在尝试从XDocument读取XML时遇到问题，将Elements转换为实际的Class对象。我不使用XmlSerialization的原因是因为我需要使用PropertyGrid。

不能让它自己在课堂上创造孩子。

错误

  System.NullReferenceException occurred
  HResult=0x80004003
  Message=Object reference not set to an instance of an object.
  Source=XmlTest2
  StackTrace:
   at XmlTest2.Program.Main(String[] args) in Program.cs:line 22

var list = q.GetElementsByClass<Targets>();
foreach (var p in list)
{
    Console.WriteLine(p.grouping.name);
}

这将有效

var list = q.GetElementsByClass<Grouping>();
foreach (var p in list)
{
    Console.WriteLine(p.name);
}

完整的代码和XML位于此处 XMLFile1.xml Program.cs

public T[] GetElementsByClass<T>() where T : class, new()
{
    Assembly asm = Assembly.GetExecutingAssembly();
    var typeName = typeof(T).Name;
    var type = asm.GetTypes().First(t => t.Name == typeName);
    if (type == null) throw new ArgumentNullException(nameof(type));

    return _doc.Descendants(_parent)
        .Select(item =>
        {
            var p = Activator.CreateInstance(type) as T;
            foreach (var prop in item.Descendants())
            {
                var pi = p.GetType().GetProperty(prop.Name.LocalName);
                if (pi == null) continue;

                object newVal = Convert.ChangeType(prop.Value, pi.PropertyType);
                pi.SetValue(p, newVal, null);
            }

            return p;
        }).ToArray();
}