如何获取ListBox中的项目索引？

int selectedIndex = listBox1.SelectedIndex;

private void listBox1_SelectedIndexChanged(object sender, EventArgs e)
{
    int selectedIndex = listBox1.SelectedIndex;
    // 处理选中项目的索引
}

private void listBox1_ItemDataBound(object sender, ListItemEventArgs e)
{
    int itemIndex = e.Item.ItemIndex;
    // 处理项目索引
}