如何获取列表框中的项目的索引

Question

If I have a listbox Item , how do I get its index in a list? I have a databound application which lists out data that a user has previously saved. However, I want to be able to delete particular data in the list using a contextMenu .

So how do I get the list index of an item that was held to bring up the context menu?

Answer 1

为什么不访问控件的SelectedIndex属性 （MSDN）？

Answer 2

However, I want to be able to delete particular data in the list using a ContextMenu.

You can bind the item directly to the ContextMenu as a CommandParameter , for your delete command. This is a much better approach to the problem.

<ListBox ItemsSource="{Binding UserItems}">
    <ListBox.ItemTemplate>
        <DataTemplate>
            <StackPanel>
                <!-- Attach the ContextMenu to the top container in your ItemTemplate. -->
                <toolkit:ContextMenuService.ContextMenu>
                    <toolkit:ContextMenu>
                        <!-- Here we bind the current item to the RemoveCommand -->
                        <toolkit:MenuItem Command="{Binding RemoveCommand}"
                                          CommandParameter="{Binding}"
                                          Header="remove item" />
                    </toolkit:ContextMenu>
                </toolkit:ContextMenuService.ContextMenu>
                <!-- The actual DataTemplate -->
                <TextBlock Text="{Binding SomeValue}" />
            </StackPanel>
        </DataTemplate>
    </ListBox.ItemTemplate>
</ListBox>