.net - Outlook 2013 VSTO - 当前资源管理器的事件不会被触发

Question

Explorer 对象的事件未触发的可能原因是什么？我使用下面的简单代码，只需注册所有 Explorer 对象的事件。我总是在调试窗口中看到一次 Init new Explorer! 行，因此有一个 Explorer 对象。然后，当我在 Outlook 中单击、从邮件 View 切换到日历 View 、选择项目、切换回来、切换到联系人时……我只得到一些(!)第一个事件，无法确定是哪个事件。几秒钟后，尽管不断单击并更改 View ，但我没有收到更多事件。这里出了什么问题？

private void ThisAddInStartup(object sender, System.EventArgs e)
{
    foreach (var exp in this.Application.Explorers)
    {
        this.ExplorersOnNewExplorer(exp as Explorer);
    }
    this.Application.Explorers.NewExplorer += this.ExplorersOnNewExplorer;
}

private void ExplorersOnNewExplorer(Explorer currentExplorer)
{
    Debug.WriteLine("Init new Explorer!");

    currentExplorer.BeforeViewSwitch += this.CurrentExplorerOnBeforeViewSwitch;
    currentExplorer.BeforeFolderSwitch += this.CurrentExplorerOnBeforeFolderSwitch;
    currentExplorer.SelectionChange += this.CurrentExplorerOnSelectionChange;
    currentExplorer.ViewSwitch += this.CurrentExplorerOnFolderSwitch;
    currentExplorer.FolderSwitch += this.CurrentExplorerOnFolderSwitch;
}
private void CurrentExplorerOnBeforeFolderSwitch(object newFolder, ref bool cancel)
{
    Debug.WriteLine("BeforeFolderSwitch!");
}

private void CurrentExplorerOnBeforeViewSwitch(object newView, ref bool cancel)
{
    Debug.WriteLine("BeforeViewSwitch!");
}

private void CurrentExplorerOnFolderSwitch()
{
    Debug.WriteLine("CurrentExplorerOnFolderOrViewSwitch!");
}

private void CurrentExplorerOnSelectionChange()
{
    Debug.WriteLine("Selection changed!");
}

Answer 1

触发事件的对象必须保持事件状态。在您的情况下，您在作为参数传递的对象上设置事件处理程序。一旦超出范围，它就会被释放，并且不会触发任何事件。 Explorer 和 Explorer 都必须在类级别声明。

您可能还想跟踪 Explorer.Close 事件，以从您正在监视的对象列表中删除 Explorer 对象。

private List<Explorer> _explorers = new List<Explorer>();
private Explorer explorer;
private void ThisAddInStartup(object sender, System.EventArgs e)
{
    _explorers = this.Application.Explorers;
    foreach (var exp in _explorers)
    {
        this.ExplorersOnNewExplorer(exp as Explorer);
    }
    _explorers.NewExplorer += this.ExplorersOnNewExplorer;
}

private void ExplorersOnNewExplorer(Explorer currentExplorer)
{
    _explorers.Add(currentExplorer);
    Debug.WriteLine("Init new Explorer!");

    currentExplorer.BeforeViewSwitch += this.CurrentExplorerOnBeforeViewSwitch;
    currentExplorer.BeforeFolderSwitch += this.CurrentExplorerOnBeforeFolderSwitch;
    currentExplorer.SelectionChange += this.CurrentExplorerOnSelectionChange;
    currentExplorer.ViewSwitch += this.CurrentExplorerOnFolderSwitch;
    currentExplorer.FolderSwitch += this.CurrentExplorerOnFolderSwitch;
}