使用If Else-If语句声明不同类型的变量

use*_*963 2 c# types casting

我有一个方法,根据TreeView中单击的项目接收事件.

我可以以完全相同的方式向TreeView和TreeViewItem添加项目,因此尝试item根据state.sender类型分配为TreeView或TreeViewItem .但是,目前我能使其工作的唯一方法是首先将项目指定为对象.

private void ProcessEvent(Events.GetEventsResp resp, CustomAsyncStateContainer state)
{
    object item = new object();   //must be a better way than this?
    if (state.sender is TreeViewItem)
        item = (TreeViewItem)state.sender;

    else if (state.sender is TreeView)
        item = (TreeView)state.sender;

     //other code
}
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我认为这被称为拆箱?有没有更好的方法来做我正在尝试的事情?

编辑:下面是剩下的代码.在提出问题时我还没有完成它的写作,现在已经意识到object item = new object();在这种情况下不会起作用.

private void DisplayGetEvent(Events.GetEventsResp resp, CustomAsyncStateContainer state)
{
    object node = new object();
    if (state.sender is TreeViewItem)
        node = (TreeViewItem)state.sender;

    else if (state.sender is TreeView)
        node = (TreeView)state.sender;

    if (resp.eventItems != null)
    {
        Events.UXEvent[] eventItems = resp.eventItems;
        Array.Sort(eventItems, new UXWrapper.UXEventComparer());

        int itemCount = eventItems.Length;
        TreeViewItem tvItem = new TreeViewItem;
        for (int i = 0; i < itemCount; i++)
        {

            tvItem.Header = eventItems[i].name;
            tvItem.Tag = eventItems[i];

            node.Items.Add(tvItem);

        }

    }
}
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小智 5

TreeView并且TreeViewItem两者都来自ItemsControl,并且添加项目是使用已经可用的方法完成的,因此您应该能够简单地使用

private void ProcessEvent(Events.GetEventsResp resp, CustomAsyncStateContainer state)
{
    var item = (ItemsControl)state.sender;

    // add to item
}
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