WPF/C#：如何从列表框中一键选择？

<ListBox x:Name="listBox">
    <ListBoxItem>选项1</ListBoxItem>
    <ListBoxItem>选项2</ListBoxItem>
    <ListBoxItem>选项3</ListBoxItem>
</ListBox>

var selectedItem = listBox.SelectedItem as ListBoxItem;
if (selectedItem != null)
{
    // 执行相关操作
}

private void SelectButton_Click(object sender, RoutedEventArgs e)
{
    var selectedItem = listBox.SelectedItem as ListBoxItem;
    if (selectedItem != null)
    {
        // 执行相关操作
    }
}