Как вызвать NetUserGetInfo из Visual Basic
(из базы знаний Майкрософт, идентификатор статьи 151774)
Функция NetUserGetInfo - это API-интерфейс Windows NT только для Unicode. Последний параметр этой функции - указатель на указатель на структуру, члены которой содержат данные DWORD и указатели на строки Unicode. Для правильного вызова этой функции из приложения Visual Basic вам необходимо отменить ссылку на указатель, возвращаемый функцией, а затем преобразовать строку Visual Basic в строку Unicode и наоборот. Эта статья иллюстрирует эти методы в примере, который вызывает NetUserGetInfo для извлечения структуры USER_INFO_3 из приложения Visual Basic.
В приведенном ниже примере функция Win32 RtlMoveMemory используется для отмены ссылки на указатель, возвращенный вызовом NetUserGetInfo.
Пошаговый пример
- Запустите Visual Basic. Если Visual Basic уже запущен, в меню «Файл» выберите «Новый проект».
Form1
создается по умолчанию.
- Добавить кнопку управления
Command1
к Form1
.
- Добавьте следующий код в раздел «Общие декларации»
Form1
:
' definitions not specifically declared in the article:
' the servername and username params can also be declared as Longs,
' and passed Unicode memory addresses with the StrPtr function.
Private Declare Function NetUserGetInfo Lib "netapi32" _
(ByVal servername As String, _
ByVal username As String, _
ByVal level As Long, _
bufptr As Long) As Long
Const NERR_Success = 0
Private Declare Sub MoveMemory Lib "kernel32" Alias _
"RtlMoveMemory" (pDest As Any, pSource As Any, ByVal dwLength As Long)
Private Declare Function lstrlenW Lib "kernel32" (lpString As Any) As Long
' Converts a Unicode string to an ANSI string
' Specify -1 for cchWideChar and 0 for cchMultiByte to return string length.
Private Declare Function WideCharToMultiByte Lib "kernel32" _
(ByVal codepage As Long, _
ByVal dwFlags As Long, _
lpWideCharStr As Any, _
ByVal cchWideChar As Long, _
lpMultiByteStr As Any, _
ByVal cchMultiByte As Long, _
ByVal lpDefaultChar As String, _
ByVal lpUsedDefaultChar As Long) As Long
Private Declare Function NetApiBufferFree Lib "netapi32" _
(ByVal Buffer As Long) As Long
' CodePage
Const CP_ACP = 0 ' ANSI code page
Private Type USER_INFO_3
usri3_name As Long 'LPWSTR in SDK
usri3_password As Long 'LPWSTR in SDK
usri3_password_age As Long 'DWORD in SDK
usri3_priv As Long 'DWORD in SDK
usri3_home_dir As Long 'LPWSTR in SDK
usri3_comment As Long 'LPWSTR in SDK
usri3_flags As Long 'DWORD in SDK
usri3_script_path As Long 'LPWSTR in SDK
usri3_auth_flags As Long 'DWORD in SDK
usri3_full_name As Long 'LPWSTR in SDK
usri3_usr_comment As Long 'LPWSTR in SDK
usri3_parms As Long 'LPWSTR in SDK
usri3_workstations As Long 'LPWSTR in SDK
usri3_last_logon As Long 'DWORD in SDK
usri3_last_logoff As Long 'DWORD in SDK
usri3_acct_expires As Long 'DWORD in SDK
usri3_max_storage As Long 'DWORD in SDK
usri3_units_per_week As Long 'DWORD in SDK
usri3_logon_hours As Long 'PBYTE in SDK
usri3_bad_pw_count As Long 'DWORD in SDK
usri3_num_logons As Long 'DWORD in SDK
usri3_logon_server As Long 'LPWSTR in SDK
usri3_country_code As Long 'DWORD in SDK
usri3_code_page As Long 'DWORD in SDK
usri3_user_id As Long 'DWORD in SDK
usri3_primary_group_id As Long 'DWORD in SDK
usri3_profile As Long 'LPWSTR in SDK
usri3_home_dir_drive As Long 'LPWSTR in SDK
usri3_password_expired As Long 'DWORD in SDK
End Type
Private Sub Command1_Click()
Dim lpBuf As Long
Dim ui3 As USER_INFO_3
' Replace "Administrator" with a valid Windows NT user name.
If (NetUserGetInfo("", StrConv("Administrator", vbUnicode), 3, _
uf) = NERR_Success) Then
Call MoveMemory(ui3, ByVal lpBuf, Len(ui3))
MsgBox GetStrFromPtrW(ui3.usri3_name)
Call NetApiBufferFree(ByVal lpBuf)
End If
End Sub
' Returns an ANSI string from a pointer to a Unicode string.
Public Function GetStrFromPtrW(lpszW As Long) As String
Dim sRtn As String
sRtn = String$(lstrlenW(ByVal lpszW) * 2, 0) ' 2 bytes/char
' WideCharToMultiByte also returns Unicode string length
' sRtn = String$(WideCharToMultiByte(CP_ACP, 0, ByVal lpszW, -1, 0, 0, 0, 0), 0)
Call WideCharToMultiByte(CP_ACP, 0, ByVal lpszW, -1, ByVal sRtn, Len(sRtn), 0, 0)
GetStrFromPtrW = GetStrFromBufferA(sRtn)
End Function
' Returns the string before first null char encountered (if any) from an ANSI string.
Public Function GetStrFromBufferA(sz As String) As String
If InStr(sz, vbNullChar) Then
GetStrFromBufferA = Left$(sz, InStr(sz, vbNullChar) - 1)
Else
' If sz had no null char, the Left$ function
' above would return a zero length string ("").
GetStrFromBufferA = sz
End If
End Function
Я бы порекомендовал переформулировать это в модуль, а не встраивать в саму форму. Я успешно использовал это в Access в прошлом.