How do I integrate UAC into my VB6 program? - visual-studio

Question

I need some code that will add the admin rights icon to command buttons and display the prompt when such buttons are clicked. How can I do this in VB6? Some actions require admin rights because they replace files and stuff where Windows Vista/7 don't allow the program normal access to the files.

Answer 1

Here's a VB6 example of ShellExecuteEx that will allow you to optionally execute any process with admin permissions. You can drop this into a module or class.
Option Explicit
Private Const SEE_MASK_DEFAULT = &H0
Public Enum EShellShowConstants
essSW_HIDE = 0
essSW_SHOWNORMAL = 1
essSW_SHOWMINIMIZED = 2
essSW_MAXIMIZE = 3
essSW_SHOWMAXIMIZED = 3
essSW_SHOWNOACTIVATE = 4
essSW_SHOW = 5
essSW_MINIMIZE = 6
essSW_SHOWMINNOACTIVE = 7
essSW_SHOWNA = 8
essSW_RESTORE = 9
essSW_SHOWDEFAULT = 10
End Enum
Private Type SHELLEXECUTEINFO
cbSize As Long
fMask As Long
hwnd As Long
lpVerb As String
lpFile As String
lpParameters As String
lpDirectory As String
nShow As Long
hInstApp As Long
lpIDList As Long 'Optional
lpClass As String 'Optional
hkeyClass As Long 'Optional
dwHotKey As Long 'Optional
hIcon As Long 'Optional
hProcess As Long 'Optional
End Type
Private Declare Function ShellExecuteEx Lib "shell32.dll" Alias "ShellExecuteExA" (lpSEI As SHELLEXECUTEINFO) As Long
Public Function ExecuteProcess(ByVal FilePath As String, ByVal hWndOwner As Long, ShellShowType As EShellShowConstants, Optional EXEParameters As String = "", Optional LaunchElevated As Boolean = False) As Boolean
Dim SEI As SHELLEXECUTEINFO
On Error GoTo Err
'Fill the SEI structure
With SEI
.cbSize = Len(SEI) ' Bytes of the structure
.fMask = SEE_MASK_DEFAULT ' Check MSDN for more info on Mask
.lpFile = FilePath ' Program Path
.nShow = ShellShowType ' How the program will be displayed
.lpDirectory = PathGetFolder(FilePath)
.lpParameters = EXEParameters ' Each parameter must be separated by space. If the lpFile member specifies a document file, lpParameters should be NULL.
.hwnd = hWndOwner ' Owner window handle
' Determine launch type (would recommend checking for Vista or greater here also)
If LaunchElevated = True Then ' And m_OpSys.IsVistaOrGreater = True
.lpVerb = "runas"
Else
.lpVerb = "Open"
End If
End With
ExecuteProcess = ShellExecuteEx(SEI) ' Execute the program, return success or failure
Exit Function
Err:
' TODO: Log Error
ExecuteProcess = False
End Function
Private Function PathGetFolder(psPath As String) As String
On Error Resume Next
Dim lPos As Long
lPos = InStrRev(psPath, "\")
PathGetFolder = Left$(psPath, lPos - 1)
End Function

Answer 2

Code examples can really run on, but here is a trivial one showing the "second instance of me" approach.
The program has a startup static module with a few public functions including an "elevated operation" handler, and a Form with just one CommandButton on it:
Module1.bas
Option Explicit
Private Const BCM_SETSHIELD As Long = &H160C&
Private Declare Sub InitCommonControls Lib "comctl32" ()
Private Declare Function IsUserAnAdmin Lib "shell32" () As Long
Private Declare Function SendMessage Lib "user32" _
Alias "SendMessageA" ( _
ByVal hWnd As Long, _
ByVal wMsg As Long, _
ByVal wParam As Long, _
ByRef lParam As Any) As Long
Private Declare Function ShellExecute Lib "shell32" _
Alias "ShellExecuteA" ( _
ByVal hWnd As Long, _
ByVal lpOperation As String, _
ByVal lpFile As String, _
ByVal lpParameters As String, _
ByVal lpDirectory As String, _
ByVal nShowCmd As VbAppWinStyle) As Long
Private mblnIsElevated As Boolean
Public Function IsElevated() As Boolean
IsElevated = mblnIsElevated
End Function
Public Sub OperationRequiringElevation(ByRef Params As Variant)
MsgBox "Insert logic here for: " & vbNewLine _
& Join(Params, vbNewLine)
End Sub
Public Sub RequestOperation( _
ByVal hWnd As Long, _
ByVal Focus As VbAppWinStyle, _
ByRef Params As Variant)
ShellExecute hWnd, "runas", App.EXEName & ".exe", _
Join(Params, " "), CurDir$(), Focus
End Sub
Public Sub SetShield(ByVal hWnd As Long)
SendMessage hWnd, BCM_SETSHIELD, 0&, 1&
End Sub
Private Sub Main()
If Len(Command$()) > 0 Then
'Assume we've been run elevated to execute an operation
'specified as a set of space-delimited strings.
OperationRequiringElevation Split(Command$(), " ")
Else
mblnIsElevated = IsUserAnAdmin()
InitCommonControls
Form1.Show
End If
End Sub
Form1.frm
Option Explicit
Private Sub Command1_Click()
Dim Params As Variant
Params = Array("ReplaceFile", "abc", "123")
If IsElevated() Then
OperationRequiringElevation Params
Else
RequestOperation hWnd, vbHide, Params
End If
End Sub
Private Sub Form_Load()
If Not IsElevated() Then
SetShield Command1.hWnd
End If
End Sub
The application has a simple "asInvoker" manifest selecting the Common Controls 6.0 assembly.

Answer 3

First, take the code that runs when someone clicks the button, and put it in a separate exe. Change your button-click code to launch the exe using ShellExecute. Second, build external manifests for each new exe and have it specify requireAdministrator. Third, send your buttons the BCM_SETSHIELD message (you will probably have to look up the numerical value of the message ID) to make the shield appear on them.

Answer 4

Move all of the code that requires elevation into external processes.
Send your buttons the BCM_SETSHIELD message to add the shield icon.
Embed manifests into those processes, telling Windows that they require elevation. See below.
In order to force Vista and higher to run a VB6 exe as administrator in UAC, you must embed a manifest xml as a resource inside of it. Steps follow;
Create the manifest file. Name it "YourProgram.exe.manifest" it should contain the following. The important line is the "requestedExecutionLevel". Change the attributes in to match your exe.
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>>
<assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0">
<assemblyIdentity
version="1.0.0.0"
processorArchitecture="X86"
name="YourProgram"
type="win32"
>
<description>application description</description>
<trustInfo xmlns="urn:schemas-microsoft-com:asm.v2">
<security
<requestedPrivileges>
<requestedExecutionLevel level="requireAdministrator" uiAccess="false"/>
</requestedPrivileges>
</security>
</trustInfo>
</assembly>
Create a file named "YourProgram.exe.manifest.rc". It should contain the following.
#define CREATEPROCESS_MANIFEST_RESOURCE_ID 1
#define RT_MANIFEST 24 CREATEPROCESS_MANIFEST_RESOURCE_ID
RT_MANIFEST "YourProgram.exe.manifest"
Compile your resource using rc.exe. It is located by default in C:\Program Files\Microsoft Visual Studio\COMMON\MSDev98\Bin. This will create a file called YourProgram.exe.manifest.RES. The syntax is;
rc /r YourProgram.exe.manifest.rc
Add the .RES file to your project. Do this using the Resource Editor Add-In in VB6. The icon on the toolbar looks like green blocks. If you do not have the icon, make sure it is enabled in the addin manager. If it is not in the addin manager, you need to regsvr32 on C:\Program Files\Microsoft Visual Studio\VB98\Wizards\Resedit.dll. Once you've got the resource editor open, click open and select your .RES file.
Compile your project.
To double check that the manifest was embedded properly, you can use a tool called InspectExe. In explorer, go to the properties of the exe, and if the manifest was embedded you should have a manifest tab (.Net assemblies will also have this manifest tab).
Try running your program on Vista or later. If UAC is indeed enabled, it should come up with the prompt right away.