如何在异步调用时让 ManagementObjectSearcher 返回 ManagementObjectCollection？

Question

这是我拥有的一些代码，它有效：

SelectQuery query = new SelectQuery("Win32_SystemDriver")
{
    Condition = "Name = 'FTDIBUS'"
};
ManagementObjectSearcher searcher = new ManagementObjectSearcher(query);
ManagementObjectCollection drivers = searcher.Get();

但我想异步调用它。 我看到 searcher.Get() 有一个异步运行的重载，它通过传入ManagementOperationObserver实例来工作。

不过，我不知道如何真正让它返回相同的集合。 这是我到目前为止所拥有的：

private bool _completed = false;

public void QueryDrivers()
{
    SelectQuery query = new SelectQuery("Win32_SystemDriver")
    {
        Condition = "Name = 'FTDIBUS'"
    };
    ManagementObjectSearcher searcher = new ManagementObjectSearcher(query);
    ManagementOperationObserver results = new ManagementOperationObserver();
    results.Completed += new CompletedEventHandler(QueryComplete);
    searcher.Get(results);

    while (!_completed)
    {
        Thread.Sleep(100);
    }

    // how do i access my ManagementObjectCollection here?
    //ManagementObjectCollection drivers = ????
}

private void QueryComplete(object sender, CompletedEventArgs e)
{
    _completed = true;
}

Answer 1

订阅 ObjectReady，您将在那里一一收到所有管理对象：

results.ObjectReady+= Obs_ObjectReady;

...

// this will get called as many times as you have objects in the expected collection
private void Obs_ObjectReady(object sender, ObjectReadyEventArgs e)
{
   var obj = e.NewObject as ManagementObject;
}