How to identify the clicked button belongs to which listbox item?

Question

In WPF programming, I have a problem to write the button click event handler. Because the button is inside a listbox item(a part of datatemplate), and when the button is cli

Answer 1

ListBox.selectedItem and listbox.SelectedIndex will be set as part of clicking the button.

Assuming the items in the list box are say type MyListBoxItem

void SomeButtonClick(Object sender, EventArgs e)
{
  ListBox lb = sender as ListBox
  if (lb != null)
  {
    MyListBoxItem item = lb.SelectedItem As MyListBoxItem;
    if (item != Null)
    {
      item.MethodRelatedToButton(); // maybe
    }
  }
}

Amplified as requested