WCF使用泛型方法的问题

public IList getModelList(string type, string SQL, List<string> list)
{
try
{
IList Mlist = new List<object>();
IDataReader dr = getDataReader(SQL, list);
while (dr.Read())
{
object obj = this.GetType().GetMethods().First((p) => p.IsGenericMethod && p.Name == "LoadFromReader").MakeGenericMethod(Helper.types[type]).Invoke(this, new object[] { dr });
Mlist.Add(obj);
}
return Mlist;
}
catch (Exception ex)
{
return null;
}
}

[OperationContract]

[ServiceKnownType("GetKnownTypes", typeof(Helper))]

IList getModelList(string type, string SQL, List<string> list);

 

 

public static class Helper
{
public static Dictionary<string, Type> types = Assembly.LoadFrom(AppDomain.CurrentDomain.BaseDirectory + "XXX.Model.dll").GetTypes().ToDictionary(t => t.Name);

public static IEnumerable<Type> GetKnownTypes(ICustomAttributeProvider provider)
{
return types.Select(t=>t.Value);
}
}