Help, cannot populate a list box when calling a thread function using AfxBeginThread

Hello,

I am having issues getting my worker thread to function properly. I am working with visual c++ 6 and I am unsure that this is the correct forum to post in but I could not find another that seemed to better suit my question.

I am trying to initiate a thread to populate a list box when I click on a button. Once I figure out I will be populating the list box with more complex code, but if I can't even get this to work, I can't move forward on the next part. I am trying to make the following code work but it is obviously not correct:

void CDialogDlg::OnButton1()
{
AfxBeginThread(CDialogDlg::MyThreadFunction,(LPVOI D)this);
}

UINT CDialogDlg::MyThreadFunction(LPVOID lparam)
{
m_listbox.AddString("testfromfunction");
return 0;
}

This code produces the following error:
'AfxBeginThread':none of the 2 overloads can convert parameter 1 from type 'unsigned int (void *)'

If I change it to the following code, AfxBeginThread works just fine, but I cannot populate the listbox because the MyThreadFunction does not know anything about the m_listbox variable, let alone the AddString member function:

void CDialogDlg::OnButton1()
{
AfxBeginThread(MyThreadFunction,(LPVOID)this);
}

UINT MyThreadFunction(LPVOID lparam)
{
AfxMessageBox("testfromfunction");
return 0;
}

Any help would be greatly appreciated,

Thanks