Container Template Specialization

Sorry, but I can not find even the direction to solve the situation. The question is: There is a container class that is defined through a template.

 template <typename T1, typename T2> 

 public ref class FormContainer 

 {
 private:
   T1 ^ container;
   List <T2 ^> ^ elements;
   ...
   Int32 currentContainerItem ();

 public:
   property Int32 currentElementId
   {
     Int32 get
     {
       return currentContainerItem ();
     }
   }
   ...
 };

Different types of containers will be used for T1 (ComboBox, ListBox, DataGridView). I need to get the current item in the current container. I see no way other than to specialize the method for this action - currentContainerItem . The method will be valid for each type of container.

My implementation attempt (for ComboBox) turns out to be erroneous, but I can't understand why ...

 template <typename T2>
 inline Int32 FormContainer <ComboBox, T2> :: currentContainerIndex ()
 {
     return container-> SelestedIndex;
 }

I do not want local gurus to write how to make the right decision. I ask you to direct my brain in the right direction and suggest the cause of the error.