基于this blog post,我已经写了一些代码来检测USB设备:设备接口活动,获取设备名称
PDevBroadcastDeviceInterface = ^DEV_BROADCAST_DEVICEINTERFACE;
DEV_BROADCAST_DEVICEINTERFACE = record
dbcc_size : DWORD;
dbcc_devicetype : DWORD;
dbcc_reserved : DWORD;
dbcc_classguid : TGUID;
dbcc_name : char;
end;
.
.
.
procedure TUsbClass.RegisterUsbHandler;
var rDbi : DEV_BROADCAST_DEVICEINTERFACE;
iSize : integer;
begin
iSize := SizeOf(DEV_BROADCAST_DEVICEINTERFACE);
ZeroMemory(@rDbi,iSize);
rDbi.dbcc_size := iSize;
rDbi.dbcc_devicetype := USB_INTERFACE;
rDbi.dbcc_reserved := 0;
rDbi.dbcc_classguid := GUID_DEVINTF_USB_DEVICE;
rDbi.dbcc_name := #0;
RegisterDeviceNotification(FHandle,@rDbi,DEVICE_NOTIFY_WINDOW_HANDLE);
end;
procedure TUsbClass.WMDeviceChange(var AMessage : TMessage);
var iDevType : integer;
sDevString,sDevType,
sDriverName,sFriendlyName : string;
pData : PDevBroadcastDeviceInterface;
pVol : PDEV_BROADCAST_VOLUME;
begin
if (AMessage.wParam = USB_INSERTION) or
(AMessage.wParam = USB_REMOVAL) then begin
pData := PDevBroadcastDeviceInterface(AMessage.LParam);
iDevType := pData^.dbcc_devicetype;
if iDevType = USB_VOLUME then
if Assigned(FOnDevVolumeEvent) then begin
...
end
else
else
// Is it a USB Interface Device ?
if iDevType = USB_INTERFACE then begin
sDevString := PChar(@pData^.dbcc_name);
...
end;
end;
end;
一切正常,我做当USB设备插入接收事件,但问题sDevString
总是一个空字符串。我也尝试检测WPD设备(通过将rDbi.dbcc_classguid
设置为正确的GUID值),并且它工作正常,但我总是得到一个空字符串sDevString
。我怎样才能得到正确的设备名称?
我从博客文章中添加了PDevBroadcastDeviceInterface的定义。 –