列表框项删除 [英] ListBox Item Removal

问题描述

我有一个管理配置集的 WPF 窗口，它允许用户编辑配置集(编辑按钮)和删除配置集(删除按钮).该窗口有一个 ListBox 控件，该控件按名称列出配置集，其 ItemsSource 具有与配置集列表的绑定集.

I have a WPF window that manages sets of configurations and it allows users to edit a configuration set (edit button) and to remove a configuration set (remove button). The window has a ListBox control that lists the configuration sets by name and its ItemsSource has a binding set to a list of configuration sets.

我正在尝试删除窗口代码隐藏文件中的项目..

I'm trying to remove the item in the code behind file for the window..

private void RemoveButton_Click(object sender, RoutedEventArgs e)
{
    var removedItems = configSetListBox.SelectedItems;

    foreach(ConfigSet removedItem in removedItems)
    {
        configSetListBox.Items.Remove(removedItem);
    }
}

我的代码产生了一个无效的操作异常，说明改为使用 ItemsControl.ItemsSource 访问和修改元素".我应该访问什么属性才能从 ListBox 中正确删除项目?或者在 WPF 中是否有更优雅的方式来处理这个问题?如果你愿意的话，我的实现有点像 WinForm :)

My code yields an invalid operation exception stating "Access and modify elements with ItemsControl.ItemsSource instead." What property should I be accessing to properlyremove items from the ListBox? Or is there possibly a more elegant way to handle this in WPF? My implementation is a bit WinForm-ish if you will :)

解决方案

private void RemoveButton_Click(object sender, RoutedEventArgs e)
{   
    foreach(ConfigSet removedItem in configSetListBox.SelectedItems)
    {
        (configSetListBox.ItemsSource as List<ConfigSet>).Remove(removedItem);
    }
    configSetListBox.Items.Refresh();
}

在我的例子中，我有一个 List 作为 ItemSource 绑定类型，所以我必须以这种方式进行转换.如果不刷新 Items 集合，ListBox 不会更新；所以这是我的解决方案所必需的.

In my case I had a List as the ItemSource binding type so I had to cast it that way. Without refreshing the Items collection, the ListBox doesn't update; so that was necessary for my solution.

推荐答案

使用:

private void RemoveButton_Click(object sender, RoutedEventArgs e)
{
  foreach(ConfigSet item in this.configSetListBox.SelectedItems)
  {
      this.configSetListBox.ItemsSource.Remove(item); // ASSUMING your ItemsSource collection has a Remove() method
  }
}

注意:我使用这个.就是这样，因为它更明确 - 它还有助于查看对象在类命名空间中，而不是我们所在方法中的变量 - 尽管在这里很明显.

Note: my use of this. is just so it as it is more explicit - it also helps one see the object is in the class namespace as opposed to variable in the method we are in - though it is obvious here.

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