c# - 一次只检查一个 ListViewItem

Question

我正在使用 Compact Framework 开发一个智能设备项目。

我有一个 ListView，其中包含多个可检查的 ListViewItem:属性 CheckBoxes 为真。我一次只需要检查一个 ListViewItem，所以我订阅了 ItemCheck 事件:

// I need to know the last item checked
private ListViewItem lastItemChecked;

private void listView_ItemCheck(object sender, ItemCheckEventArgs e)
{
    if (lastItemChecked != null && lastItemChecked.Checked)
    {
        /* I need to do the following to prevent infinite recursion:
        i.e. subscribe and then unsubscribe the ItemCheck event. */
        listView.ItemCheck -= listView_ItemCheck;
        lastItemChecked.Checked = false;
        listView.ItemCheck += listView_ItemCheck;
    }

    lastItemChecked = listView.Items[e.Index];
}

是否有更好的方法来防止无限递归和 Stack Overflow？

Answer 1

好吧，我认为可能比处理 EventHandler 更好的是检查 lastItemCheck 是否是来自 EventArgs 的当前项目。像这样:

// I need to know the last item checked
private ListViewItem lastItemChecked;

private void listView_ItemCheck(object sender, ItemCheckEventArgs e)
{
    // if we have the lastItem set as checked, and it is different
    // item than the one that fired the event, uncheck it
    if (lastItemChecked != null && lastItemChecked.Checked
        && lastItemChecked != listView.Items[e.Index] )
    {
        // uncheck the last item and store the new one
        lastItemChecked.Checked = false;
    }

    // store current item
    lastItemChecked = listView.Items[e.Index];
}

我想你会同意，重新分配 EventHandlers 比简单地检查存储对象的引用要糟糕一些。