问只在需要时使Inno安装程序请求权限提升

EN

[Setup]
PrivilegesRequiredOverridesAllowed=commandline dialog

[Setup]
DefaultDirName={pf}\My Program

#define AppId "myapp"
#define AppName "MyApp"

#define InnoSetupReg \
  "Software\Microsoft\Windows\CurrentVersion\Uninstall\" + AppId + "_is1"
#define InnoSetupAppPathReg "Inno Setup: App Path"

[Setup]
AppId={#AppId}
PrivilegesRequired=none
...

[Code]

function IsWinVista: Boolean;
begin
  Result := (GetWindowsVersion >= $06000000);
end;

function HaveWriteAccessToApp: Boolean;
var
  FileName: string;
begin
  FileName := AddBackslash(WizardDirValue) + 'writetest.tmp';
  Result := SaveStringToFile(FileName, 'test', False);
  if Result then
  begin
    Log(Format(
      'Have write access to the last installation path [%s]', [WizardDirValue]));
    DeleteFile(FileName);
  end
    else
  begin
    Log(Format('Does not have write access to the last installation path [%s]', [
      WizardDirValue]));
  end;
end;

procedure ExitProcess(uExitCode: UINT);
  external 'ExitProcess@kernel32.dll stdcall';
function ShellExecute(hwnd: HWND; lpOperation: string; lpFile: string;
  lpParameters: string; lpDirectory: string; nShowCmd: Integer): THandle;
  external 'ShellExecuteW@shell32.dll stdcall';

function Elevate: Boolean;
var
  I: Integer;
  RetVal: Integer;
  Params: string;
  S: string;
begin
  { Collect current instance parameters }
  for I := 1 to ParamCount do
  begin
    S := ParamStr(I);
    { Unique log file name for the elevated instance }
    if CompareText(Copy(S, 1, 5), '/LOG=') = 0 then
    begin
      S := S + '-elevated';
    end;
    { Do not pass our /SL5 switch }
    if CompareText(Copy(S, 1, 5), '/SL5=') <> 0 then
    begin
      Params := Params + AddQuotes(S) + ' ';
    end;
  end;

  { ... and add selected language }
  Params := Params + '/LANG=' + ActiveLanguage;

  Log(Format('Elevating setup with parameters [%s]', [Params]));
  RetVal :=
    ShellExecute(0, 'runas', ExpandConstant('{srcexe}'), Params, '', SW_SHOW);
  Log(Format('Running elevated setup returned [%d]', [RetVal]));
  Result := (RetVal > 32);
  { if elevated executing of this setup succeeded, then... }
  if Result then
  begin
    Log('Elevation succeeded');
    { exit this non-elevated setup instance }
    ExitProcess(0);
  end
    else
  begin
    Log(Format('Elevation failed [%s]', [SysErrorMessage(RetVal)]));
  end;
end;

procedure InitializeWizard;
var
  S: string;
  Upgrade: Boolean;
begin
  Upgrade :=
    RegQueryStringValue(HKLM, '{#InnoSetupReg}', '{#InnoSetupAppPathReg}', S) or
    RegQueryStringValue(HKCU, '{#InnoSetupReg}', '{#InnoSetupAppPathReg}', S);

  { elevate }

  if not IsWinVista then
  begin
    Log(Format('This version of Windows [%x] does not support elevation', [
      GetWindowsVersion]));
  end
    else
  if IsAdminLoggedOn then
  begin
    Log('Running elevated');
  end
    else
  begin
    Log('Running non-elevated');
    if Upgrade then
    begin
      if not HaveWriteAccessToApp then
      begin
        Elevate;
      end;
    end
      else
    begin
      if not Elevate then
      begin
        WizardForm.DirEdit.Text := ExpandConstant('{localappdata}\{#AppName}');
        Log(Format('Falling back to local application user folder [%s]', [
          WizardForm.DirEdit.Text]));
      end;
    end;
  end;
end;

[Setup]
AppName=My Program
AppVersion=1.5
DefaultDirName={pf}\My Program
PrivilegesRequired=lowest

[Code]
#ifdef UNICODE
  #define AW "W"
#else
  #define AW "A"
#endif
type
  HINSTANCE = THandle;

procedure ExitProcess(uExitCode: UINT);
  external 'ExitProcess@kernel32.dll stdcall';
function ShellExecute(hwnd: HWND; lpOperation: string; lpFile: string;
  lpParameters: string; lpDirectory: string; nShowCmd: Integer): HINSTANCE;
  external 'ShellExecute{#AW}@shell32.dll stdcall';

var
  Elevated: Boolean;
  PagesSkipped: Boolean;

function CmdLineParamExists(const Value: string): Boolean;
var
  I: Integer;  
begin
  Result := False;
  for I := 1 to ParamCount do
    if CompareText(ParamStr(I), Value) = 0 then
    begin
      Result := True;
      Exit;
    end;
end;

procedure InitializeWizard;
begin
  { initialize our helper variables }
  Elevated := CmdLineParamExists('/ELEVATE');
  PagesSkipped := False;
end;

function ShouldSkipPage(PageID: Integer): Boolean;
begin
  { if we've executed this instance as elevated, skip pages unless we're }
  { on the directory selection page }
  Result := not PagesSkipped and Elevated and (PageID <> wpSelectDir);
  { if we've reached the directory selection page, set our flag variable }
  if not Result then
    PagesSkipped := True;
end;

function NextButtonClick(CurPageID: Integer): Boolean;
var
  Params: string;
  RetVal: HINSTANCE;
begin
  Result := True;
  { if we are on the directory selection page and we are not running the }
  { instance we've manually elevated, then... }
  if not Elevated and (CurPageID = wpSelectDir) then
  begin
    { pass the already selected directory to the executing parameters and }
    { include our own custom /ELEVATE parameter which is used to tell the }
    { setup to skip all the pages and get to the directory selection page }
    Params := ExpandConstant('/DIR="{app}" /ELEVATE');
    { because executing of the setup loader is not possible with ShellExec }
    { function, we need to use a WinAPI workaround }
    RetVal := ShellExecute(WizardForm.Handle, 'runas',
      ExpandConstant('{srcexe}'), Params, '', SW_SHOW);
    { if elevated executing of this setup succeeded, then... }
    if RetVal > 32 then
    begin
      { exit this non-elevated setup instance }
      ExitProcess(0);
    end
    else
    { executing of this setup failed for some reason; one common reason may }
    { be simply closing the UAC dialog }
    begin
      { handling of this situation is upon you, this line forces the wizard }
      { stay on the current page }
      Result := False;
      { and possibly show some error message to the user }
      MsgBox(Format('Elevating of this setup failed. Code: %d', [RetVal]),
        mbError, MB_OK);
    end;
  end;
end;