我正在使用一段 C# 代码来检测连接的设备并列出它们。该代码应该在 kisok 计算机上运行,并帮助客户轻松访问和上传他们的文件。下面的代码可以正常工作,只是它不能识别移动设备等便携式设备。
public void WndProc(ref Message m)
{
int devType;
char c;
if (m.Msg == WM_DEVICECHANGE)
{
// WM_DEVICECHANGE can have several meanings depending on the WParam value...
switch (m.WParam.ToInt32())
{
// New device has just arrived
case DBT_DEVICEARRIVAL:
devType = Marshal.ReadInt32(m.LParam, 4);
if (devType == DBT_DEVTYP_VOLUME)
{
DEV_BROADCAST_VOLUME vol;
vol = (DEV_BROADCAST_VOLUME)
Marshal.PtrToStructure(m.LParam, typeof(DEV_BROADCAST_VOLUME));
// Get the drive letter
c = DriveMaskToLetter(vol.dbcv_unitmask);
/* rest of handler is here */
}
break;
case DBT_DEVNODES_CHANGED:
devType = Marshal.ReadInt32(m.LParam, 4); // m.LParam in this case is 0
// handle portable device
break;
}
}
}
所以连接移动设备时收到的 mWParam 等于 DBT_DEVNODES_CHANGED (0x0007) 并且 mLParam 为 0。是否可以从此事件中识别便携式设备?我可以在这里添加相关的检测 API 吗?
我已经尝试过以下 WMI 代码,但就像之前 HandleEvent 仅在连接 USB 而不是手机时触发:(
ManagementEventWatcher watcher = new ManagementEventWatcher();
WqlEventQuery query = new WqlEventQuery("SELECT * FROM Win32_VolumeChangeEvent WHERE EventType = 2");
watcher.EventArrived += new EventArrivedEventHandler(HandleEvent);
watcher.Query = query;
watcher.Start();
watcher.WaitForNextEvent();