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我发现了几个片段和 .pas 文件，它们可以检测何时插入和移除 USB 闪存驱动器。有些提供了各种好的信息，但我需要的是设备的唯一序列号，而不是卷的序列号。

我当前的 .pas 文件（我不记得我在哪里找到的）似乎也检测到了 SD 卡（我喜欢）。如果你想看看，你可以在这里找到它（它只返回驱动器号和插入/删除）：

unit UsbDetector;

interface

uses Classes;

type
  TUsbDriveChanged = procedure (Sender: TObject; Drive: string; Attached: boolean) of object;

procedure StartUsbDetector(NotifyProc: TUsbDriveChanged);
procedure StopUsbDetector;

implementation

uses Windows, Messages, Forms, SysUtils;

type
  TUSBDetector = class(TObject)
  private
    fUsbDriveChanged: TUsbDriveChanged;
  protected
    procedure DeviceChanged(Msg: UINT; wParam, lParam: Longint);
    procedure DoUsbDriveChanged(Drive: string; Attached: Boolean); dynamic;
  public
    constructor Create(NotifyProc: TUsbDriveChanged);
    destructor Destroy; override;
    property OnUsbDriveChanged: TUsbDriveChanged read fUsbDriveChanged;
  end;

var mUSBDetector: TUSBDetector;

procedure StartUsbDetector(NotifyProc: TUsbDriveChanged);
begin
  if not Assigned(mUsbDetector) then
    mUsbDetector := TUsbDetector.Create(NotifyProc);
end;

procedure StopUsbDetector;
begin
  FreeAndNil(mUsbDetector);
end;

{----------------------------------------------------------------------------}
// Device constants
const
  DBT_DEVICEARRIVAL          =  $00008000;
  DBT_DEVICEREMOVECOMPLETE   =  $00008004;
  DBT_DEVTYP_VOLUME          =  $00000002;

// Device structs
type
  _DEV_BROADCAST_HDR         =  packed record
     dbch_size:              DWORD;
     dbch_devicetype:        DWORD;
     dbch_reserved:          DWORD;
  end;
  DEV_BROADCAST_HDR          =  _DEV_BROADCAST_HDR;
  TDevBroadcastHeader        =  DEV_BROADCAST_HDR;
  PDevBroadcastHeader        =  ^TDevBroadcastHeader;

type
  _DEV_BROADCAST_VOLUME      =  packed record
     dbch_size:              DWORD;
     dbch_devicetype:        DWORD;
     dbch_reserved:          DWORD;
     dbcv_unitmask:          DWORD;
     dbcv_flags:             WORD;
  end;
  DEV_BROADCAST_VOLUME       =  _DEV_BROADCAST_VOLUME;
  TDevBroadcastVolume        =  DEV_BROADCAST_VOLUME;
  PDevBroadcastVolume        =  ^TDevBroadcastVolume;

var
  fPrevWndProc: TFNWndProc = nil;

function UsbWndProc(hWnd: HWND; Msg: UINT; wParam, lParam: Longint): Longint; stdcall;
begin
  Result := CallWindowProc(fPrevWndProc, hWnd, Msg, wParam, lParam);
  if (Msg = WM_DEVICECHANGE) and (mUsbDetector <> nil) then
    mUsbDetector.DeviceChanged(Msg, wParam, lParam);
end;

constructor TUSBDetector.Create(NotifyProc: TUsbDriveChanged);
begin
  inherited Create;
  fUsbDriveChanged := NotifyProc;
  if not Assigned(fPrevWndProc) then 
  begin
    fPrevWndProc := TFNWndProc(GetWindowLong(Application.Handle, GWL_WNDPROC));
    SetWindowLong(Application.Handle, GWL_WNDPROC, LongInt(@UsbWndProc));
  end;
end;

destructor TUSBDetector.Destroy;
begin
  //SetWindowLong(Application.Handle, GWL_WNDPROC, LongInt(@fPrevWndProc));
  inherited Destroy;
end;

procedure TUSBDetector.DeviceChanged(Msg: UINT; wParam, lParam: LongInt);
var
  lpdbhHeader: PDevBroadcastHeader;
  lpdbvData: PDevBroadcastVolume;
  dwIndex: Integer;
  lpszDrive: string;
begin
  // Get the device notification header
  lpdbhHeader := PDevBroadcastHeader(lParam);
  // Handle the message
  lpszDrive := '';
  case WParam of
    DBT_DEVICEARRIVAL:    {a USB drive was connected}
    begin
      if lpdbhHeader^.dbch_devicetype = DBT_DEVTYP_VOLUME then
      begin
        lpdbvData := PDevBroadcastVolume(lParam);
        for dwIndex := 0 to 25 do
        begin
          if (lpdbvData^.dbcv_unitmask shr dwIndex) = 1 then
          begin
            lpszDrive := lpszDrive + Chr(65 + dwIndex) + ':\';
            break;
          end;
        end;
        DoUsbDriveChanged(lpszDrive, True);
      end;
    end;
    DBT_DEVICEREMOVECOMPLETE:    {a USB drive was removed}
    begin
      if lpdbhHeader^.dbch_devicetype = DBT_DEVTYP_VOLUME then
      begin
        lpdbvData := PDevBroadcastVolume(lParam);
        for dwIndex := 0 to 25 do
        begin
          if (lpdbvData^.dbcv_unitmask shr dwIndex) = 1 then
          begin
            lpszDrive := lpszDrive + Chr(65 + dwIndex) + ':\';
            break;
          end;
        end;
        DoUsbDriveChanged(lpszDrive, False);
      end;
    end;
  end;
end;

procedure TUSBDetector.DoUsbDriveChanged(Drive: string; Attached: Boolean);
begin
  if Assigned(fUsbDriveChanged) then
    fUsbDriveChanged(Self, Drive, Attached);
end;

end.

PS 代码高亮失败。

总而言之; 插入/删除可移动设备时，获取驱动器号及其唯一序列号。也许将已经给出的代码与 WMI 调用“where Index=found_index”结合起来。

****编辑！**** 我删除了 RRUZ 给出的代码中的“where”子句。我终于找到了如何处理数组，所以我用它来查找 Capabilities[i]=7 来获取所有可移动媒体。现在我只需要将这段代码与上面的代码连接起来。我正在考虑使用 Index，但我不知道如何使用 GetDrive MapInfo。如果你能给我提供一个获取驱动器号的例子，我的问题就解决了。

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1 回答 1

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您可以使用Magenta Systems的 WMI 库，它可以消除使用 WMI 查询的大部分痛苦。免费下载包括源代码和示例项目，可让您使用 API 并查询您心中的内容。您将需要保留指向官方 Microsoft API 文档的链接，该文档将帮助您执行哪些查询以获取哪些信息……您有兴趣使用类似 SQL 的语法查询来查询类。

例如，执行查询

SELECT * FROM Win32_DiskDrive Where InterfaceType = 'USB'

返回有关当前连接到机器的所有 USB 设备的大量信息。然后，您可以使用 PNPDeviceID 作为唯一标识符。

编辑检查我手边唯一的 USB 设备返回了一个硬件序列号“u”，但看起来很长且有效的 PNPDeviceID 似乎包含一个序列号，这就是我建议该字段的原因。

编辑您可以通过对您执行查询来获取驱动器号，Win32_LogicalDisk也可以查询Win32_DiskDriveToDiskPartition其中包含和之间的Win32_DiskDrive映射Win32_DiskPartition。最后Win32_LogicalDiskToPartition，然后将逻辑磁盘映射到分区，从而使您能够将物理 USB 驱动器链接到特定驱动器号。

于 2009-12-19T00:28:40.320 回答