如何在delphi中调用WINAPI DsRoleGetPrimaryDomainInformation？

Question

我正在调用 Windows API DsRoleGetPrimaryDomainInformation，如下面的代码块所示。我想获取域林名称和域 DNS 名称。当我为域名 DNS 名称执行 ShowMessage 时，它只是显示“????”对于域林名称，它显示的是 EmptyString。

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  StdCtrls;

type
  TForm1 = class(TForm)
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;


    DSROLE_PRIMARY_DOMAIN_INFO_LEVEL = (
    DsRolePrimaryDomainInfoBasic,
    DsRoleUpgradeStatus,
    DsRoleOperationState);

  DSROLE_MACHINE_ROLE = (
    DsRole_RoleStandaloneWorkstation,
   DsRole_RoleMemberWorkstation,
  DsRole_RoleStandaloneServer,
  DsRole_RoleMemberServer,
  DsRole_RoleBackupDomainController,
  DsRole_RolePrimaryDomainController);

   PDSROLE_PRIMARY_DOMAIN_INFO_BASIC = ^DSROLE_PRIMARY_DOMAIN_INFO_BASIC;
  DSROLE_PRIMARY_DOMAIN_INFO_BASIC = record
    MachineRole: DSROLE_MACHINE_ROLE;
    Flags: ULONG; 
    DomainNameFlat: LPWSTR;
    DomainNameDns: LPWSTR;
    DomainForestName: LPWSTR;
    DomainGuid: TGUID;
  end;

  function DsRoleGetPrimaryDomainInformation(lpServer: LPCWSTR;
  InfoLevel: DSROLE_PRIMARY_DOMAIN_INFO_LEVEL; var Buffer: DSROLE_PRIMARY_DOMAIN_INFO_BASIC): DWORD; stdcall; external 'netapi32.dll';


var
  Form1: TForm1;

implementation

{$R *.DFM}


procedure TForm1.Button1Click(Sender: TObject);
var
  pBuffer : DSROLE_PRIMARY_DOMAIN_INFO_BASIC;
begin
  if not DsRoleGetPrimaryDomainInformation(nil,DsRolePrimaryDomainInfoBasic,pBuffer) = ERROR_SUCCESS then
  begin
    ShowMessage('Something is wrong!');
    exit;
  end;
  ShowMessage(pBuffer.DomainNameDns );
  ShowMessage(pBuffer.DomainForestName);
end;

end.

Answer 1

根据文档，缓冲区不是输出参数而是指针。

所以

  function DsRoleGetPrimaryDomainInformation(lpServer: LPCWSTR;
  InfoLevel: DSROLE_PRIMARY_DOMAIN_INFO_LEVEL; var Buffer: DSROLE_PRIMARY_DOMAIN_INFO_BASIC): DWORD; stdcall; external 'netapi32.dll';

需要改成

  function DsRoleGetPrimaryDomainInformation(lpServer: LPCWSTR;
  InfoLevel: DSROLE_PRIMARY_DOMAIN_INFO_LEVEL; Buffer: pDSROLE_PRIMARY_DOMAIN_INFO_BASIC): DWORD; stdcall; external 'netapi32.dll';

这是一个具有完整实现的单元。刚刚在 Delphi 6 中测试过：

unit DSRole;

{$WEAKPACKAGEUNIT}

{$HPPEMIT ''}
{$HPPEMIT '#include "dsrole.h"'}
{$HPPEMIT ''}

interface

uses
   Windows;
//
// Domain information
//
type
  _DSROLE_MACHINE_ROLE = (
    DsRole_RoleStandaloneWorkstation,
    DsRole_RoleMemberWorkstation,
    DsRole_RoleStandaloneServer,
    DsRole_RoleMemberServer,
    DsRole_RoleBackupDomainController,
    DsRole_RolePrimaryDomainController);
  {$EXTERNALSYM _DSROLE_MACHINE_ROLE}
  DSROLE_MACHINE_ROLE = _DSROLE_MACHINE_ROLE;
  {$EXTERNALSYM DSROLE_MACHINE_ROLE}
  TDsRoleMachineRole = DSROLE_MACHINE_ROLE;

//
// Previous server state
//
  _DSROLE_SERVER_STATE = (DsRoleServerUnknown, DsRoleServerPrimary, DsRoleServerBackup);
  {$EXTERNALSYM DSROLE_SERVER_STATE}
  DSROLE_SERVER_STATE = _DSROLE_SERVER_STATE;
  {$EXTERNALSYM DSROLE_SERVER_STATE}
  PDSROLE_SERVER_STATE = ^DSROLE_SERVER_STATE;
  {$EXTERNALSYM PDSROLE_SERVER_STATE}
  TDsRoleServerState = DSROLE_SERVER_STATE;

  _DSROLE_PRIMARY_DOMAIN_INFO_LEVEL = (DsRoleFiller0, DsRolePrimaryDomainInfoBasic, DsRoleUpgradeStatus, DsRoleOperationState);
  {$EXTERNALSYM _DSROLE_PRIMARY_DOMAIN_INFO_LEVEL}
  DSROLE_PRIMARY_DOMAIN_INFO_LEVEL = _DSROLE_PRIMARY_DOMAIN_INFO_LEVEL;
  {$EXTERNALSYM DSROLE_PRIMARY_DOMAIN_INFO_LEVEL}
  TDsRolePrimaryDomainInfoLevel = DSROLE_PRIMARY_DOMAIN_INFO_LEVEL;

//
// Flags to be used with the PRIMARY_DOMAIN_INFO_LEVEL structures below
//

const
  DSROLE_PRIMARY_DS_RUNNING          = $00000001;
  {$EXTERNALSYM DSROLE_PRIMARY_DS_RUNNING}
  DSROLE_PRIMARY_DS_MIXED_MODE       = $00000002;
  {$EXTERNALSYM DSROLE_PRIMARY_DS_MIXED_MODE}
  DSROLE_UPGRADE_IN_PROGRESS         = $00000004;
  {$EXTERNALSYM DSROLE_UPGRADE_IN_PROGRESS}
  DSROLE_PRIMARY_DOMAIN_GUID_PRESENT = $01000000;
  {$EXTERNALSYM DSROLE_PRIMARY_DOMAIN_GUID_PRESENT}

//
// Structure that correspond to the DSROLE_PRIMARY_DOMAIN_INFO_LEVEL
//

type
  PDSROLE_PRIMARY_DOMAIN_INFO_BASIC = ^DSROLE_PRIMARY_DOMAIN_INFO_BASIC;
  {$EXTERNALSYM PDSROLE_PRIMARY_DOMAIN_INFO_BASIC}
  _DSROLE_PRIMARY_DOMAIN_INFO_BASIC = record
    MachineRole: DSROLE_MACHINE_ROLE;
    Flags: ULONG;
    DomainNameFlat: LPWSTR;
    DomainNameDns: LPWSTR;
    DomainForestName: LPWSTR;
    DomainGuid: TGUID;
  end;

  {$EXTERNALSYM _DSROLE_PRIMARY_DOMAIN_INFO_BASIC}
  DSROLE_PRIMARY_DOMAIN_INFO_BASIC = _DSROLE_PRIMARY_DOMAIN_INFO_BASIC;
  {$EXTERNALSYM DSROLE_PRIMARY_DOMAIN_INFO_BASIC} 
  TDsRolePrimaryDomainInfoBasic = DSROLE_PRIMARY_DOMAIN_INFO_BASIC; 
  PDsRolePrimaryDomainInfoBasic = PDSROLE_PRIMARY_DOMAIN_INFO_BASIC; 

  PDSROLE_UPGRADE_STATUS_INFO = ^DSROLE_UPGRADE_STATUS_INFO; 
  {$EXTERNALSYM PDSROLE_UPGRADE_STATUS_INFO} 
  _DSROLE_UPGRADE_STATUS_INFO = record 
    OperationState: ULONG; 
    PreviousServerState: DSROLE_SERVER_STATE; 
  end;

  {$EXTERNALSYM _DSROLE_UPGRADE_STATUS_INFO} 
  DSROLE_UPGRADE_STATUS_INFO = _DSROLE_UPGRADE_STATUS_INFO; 
  {$EXTERNALSYM DSROLE_UPGRADE_STATUS_INFO} 
  TDsRoleUpgradeStatusInfo = DSROLE_UPGRADE_STATUS_INFO; 
  PDsRoleUpgradeStatusInfo = PDSROLE_UPGRADE_STATUS_INFO; 

  _DSROLE_OPERATION_STATE = (DsRoleOperationIdle, DsRoleOperationActive, DsRoleOperationNeedReboot); 
  {$EXTERNALSYM _DSROLE_OPERATION_STATE} 
  DSROLE_OPERATION_STATE = _DSROLE_OPERATION_STATE; 
  {$EXTERNALSYM DSROLE_OPERATION_STATE} 
  TDsRoleOperationState = DSROLE_OPERATION_STATE; 

  PDSROLE_OPERATION_STATE_INFO = ^DSROLE_OPERATION_STATE_INFO; 
  {$EXTERNALSYM PDSROLE_OPERATION_STATE_INFO} 
  _DSROLE_OPERATION_STATE_INFO = record 
    OperationState: DSROLE_OPERATION_STATE; 
  end; 
  {$EXTERNALSYM _DSROLE_OPERATION_STATE_INFO} 
  DSROLE_OPERATION_STATE_INFO = _DSROLE_OPERATION_STATE_INFO; 
  {$EXTERNALSYM DSROLE_OPERATION_STATE_INFO} 
  TDsRoleOperationStateInfo = DSROLE_OPERATION_STATE_INFO; 
  PDsRoleOperationStateInfo = PDSROLE_OPERATION_STATE_INFO; 

function DsRoleGetPrimaryDomainInformation(lpServer: LPCWSTR; InfoLevel: DSROLE_PRIMARY_DOMAIN_INFO_LEVEL; Buffer: pDSROLE_PRIMARY_DOMAIN_INFO_BASIC): DWORD; stdcall;
{$EXTERNALSYM DsRoleGetPrimaryDomainInformation}

procedure DsRoleFreeMemory(Buffer: pointer); stdcall;
{$EXTERNALSYM DsRoleFreeMemory}

implementation

const
  netapi32 = 'netapi32.dll';

function DsRoleGetPrimaryDomainInformation; external netapi32 name 'DsRoleGetPrimaryDomainInformation';
procedure DsRoleFreeMemory; external netapi32 name 'DsRoleFreeMemory'; 

end. 

有了这个，你只需要调用它：

uses
 DSRole;

procedure TForm1.FormCreate(Sender: TObject);
var
  pBuffer : pDSROLE_PRIMARY_DOMAIN_INFO_BASIC;
begin
  pBuffer := new( pDSROLE_PRIMARY_DOMAIN_INFO_BASIC);
  Caption := BoolToStr(DsRoleGetPrimaryDomainInformation(nil,DsRolePrimaryDomainInfoBasic,pBuffer) = ERROR_SUCCESS, True);
  FreeMem(pBuffer);
end;