在 List 的派生类上设置属性<T>使用反射在运行时实例化

Question

I am using reflection to instantiate a custom class `class MyList : MyBaseClass, IList´:

foreach (FieldInfo field in this.GetType().GetFields())
{
   if (field.FieldType.IsGenericType && field.FieldType.GetGenericTypeDefinition() == typeof(MyList<>))
   {
      var elementType = field.FieldType.GetGenericArguments()[0];
      var listType = typeof(MyList<>).MakeGenericType(elementType);
      var valueToSet= Activator.CreateInstance(listType);
      field.SetValue(this, valueToSet);
      ...
      valueToSet.MyName = field.Name; // does not work because "valueToSet" does not recognize this property
      ...
   }
}

The problem is, that the part valueToSet.MyName = field.Name does not recognize the property MyName that my custom class MyList<T> has. I also tried defining my MyList<T> as class MyList<dynamic> : MyBaseClass, IList<dynamic> but the valueToSet.MyName = field.Name part throws now the error System.ArgumentException HResult=0x80070057 Message=Object of type objects.MyList 1[System.Object] cannot be converted to type objects.MyList 1[MyNameSpace.MyObjectType1]...

Any hint on how to resolve this? I would like to keep my original declaration without dynamics
Thanks in advance!

Answer 1

There are a few ways. You can choose the one that you think is the most suitable for you.

Keep using reflection

PropertyInfo myNameProperty = listType.GetProperty("MyName");
myNameProperty.SetValue(valueToSet, field.Name);

Use dynamic :

dynamic valueToSet= Activator.CreateInstance(listType);
...
valueToSet.MyName = field.Name;

Cast to superclass

And apparently, as you said in your comments, you can declare MyName in MyBaseClass . This is an unusual thing to be able to do, but okay... Given that MyName is declared in MyBaseClass , you can cast valueToSet to MyBaseClass :

((MyBaseClass)valueToSet).MyName = field.Name;