卸载时如何获取安装路径？

Question

我的想法是让用户选择在{localappdata} 或{commonappdata} 中安装应用程序，这部分工作正常。但是，我正在使用自定义 Inno Setup 皮肤支持，这需要在安装/卸载期间加载几个函数。

我有一个DefaultAppDataFolder(): String 函数，它返回用户选择的文件夹（普通或本地应用程序数据之一），它在安装过程中运行良好。但是，当我尝试卸载该应用程序时，它会在执行时引发以下错误：

脚本错误：无法调用 proc

您可以看到，在DefaultAppDataFolder() 函数中，我以一种有点阴暗的方式获取了卸载目录，从{UninstallExe} 常量中提取了两次文件目录，也许有更好的方法来检索它？

这是我的脚本：

#define ApplicationName "MyApp"
#define ApplicationExe "app.exe"
#define ApplicationInstanceMutex "APPMUTEX"
#define InstallerFilename "install_app"
#define SkinName "Carbon.vsf"

[Setup]                                                                               
AppName={#ApplicationName}
AppVerName={#ApplicationName}
DefaultDirName={code:DefaultAppDataFolder}
DefaultGroupName={#ApplicationName}
UninstallFilesDir={code:DefaultAppDataFolder}\uninstall
UninstallDisplayName={#ApplicationName}
Compression=lzma2     
SolidCompression=yes
OutputDir=.\
DisableDirPage=yes
OutputBaseFilename={#InstallerFilename}
UninstallDisplayIcon={code:DefaultAppDataFolder}\{#ApplicationExe}
DisableProgramGroupPage=yes
AppMutex={#ApplicationInstanceMutex}
WizardImageFile=installer_images\installer-1.bmp
WizardSmallImageFile=installer_images\installer-2.bmp

[Files]
Source: "skins\VclStylesInno.dll"; DestDir: "{code:DefaultAppDataFolder}"; Flags: uninsneveruninstall ignoreversion
Source: "skins\{#SkinName}"; DestDir: "{code:DefaultAppDataFolder}"; Flags: ignoreversion
Source: "root_files\*.*"; DestDir: "{code:DefaultAppDataFolder}"; Flags: ignoreversion
Source: "client_files\*.*"; DestDir: "{code:DefaultAppDataFolder}"; Flags: ignoreversion
Source: "ssl_libs\*.*"; DestDir: "{code:DefaultAppDataFolder}"; Flags: ignoreversion

[Icons]
Name: "{group}\{#ApplicationName}"; Filename: "{code:DefaultAppDataFolder}\{#ApplicationExe}"; WorkingDir: "{code:DefaultAppDataFolder}"
Name: "{group}\Uninstall"; Filename: "{uninstallexe}"
Name: "{commondesktop}\{#ApplicationName}"; Filename: "{code:DefaultAppDataFolder}\{#ApplicationExe}"; Tasks: desktopicon

[Run]
Filename: "{code:DefaultAppDataFolder}\{#ApplicationExe}"; Description: "Launch {#ApplicationName}"; Flags: postinstall nowait runascurrentuser

[Tasks]
Name: commondir; Description: "&All users"; GroupDescription: "Install For:"; Flags: exclusive
Name: localdir; Description: "&Current user"; GroupDescription: "Install For:"; Flags: exclusive unchecked
Name: desktopicon; Description: "Create a &desktop icon"

[Code]
procedure LoadVCLStyleS(VClStyleFile: String); external 'LoadVCLStyleW@files:VclStylesInno.dll stdcall setuponly';
procedure UnLoadVCLStylesS; external 'UnLoadVCLStyles@files:VclStylesInno.dll stdcall setuponly';

procedure LoadVCLStyleU(VClStyleFile: String); external 'LoadVCLStyleW@{code:DefaultAppDataFolder}\VclStylesInno.dll stdcall uninstallonly';
procedure UnLoadVCLStylesU; external 'UnLoadVCLStyles@{code:DefaultAppDataFolder}\VclStylesInno.dll stdcall uninstallonly';

var
  ApplicationUninstalled: Boolean;
  WizardInitialized: Boolean;

function InitializeSetup(): Boolean;
var
  C1: Integer;
begin
  ExtractTemporaryFile('{#SkinName}');
  LoadVCLStyleS(ExpandConstant('{tmp}\{#SkinName}'));
  result := TRUE;
end;

procedure InitializeWizard();
begin
  WizardInitialized := TRUE;
end;

procedure DeinitializeSetup();
begin
  UnLoadVCLStylesS;
end;

function InitializeUninstall(): Boolean;
begin
  LoadVCLStyleU(ExpandConstant('{code:DefaultAppDataFolder}\{#SkinName}'));
  result := TRUE;
end;

procedure InitializeUninstallProgressForm();
begin
  ApplicationUninstalled := TRUE;
end;

procedure DeinitializeUninstall();
begin
  UnLoadVCLStylesU;
  UnloadDLL(ExpandConstant('{code:DefaultAppDataFolder}\VclStylesInno.dll'));

  if ApplicationUninstalled then
  begin
    DeleteFile(ExpandConstant('{code:DefaultAppDataFolder}\VclStylesInno.dll'));
    RemoveDir(ExpandConstant('{code:DefaultAppDataFolder}'));
  end;
end;

procedure CurUninstallStepChanged(CurUninstallStep: TUninstallStep);
var
  mres: integer;
begin
  case CurUninstallStep of
    usPostUninstall: begin
      mres := MsgBox('Do you want to delete user data?', mbConfirmation, MB_YESNO or MB_DEFBUTTON2)
      if mres = IDYES then
      begin   
        DelTree(ExpandConstant('{localappdata}\{#ApplicationName}'), TRUE, TRUE, TRUE);
        DelTree(ExpandConstant('{userappdata}\{#ApplicationName}'), TRUE, TRUE, TRUE);
      end;
    end;  
  end;
end;

function DefaultAppDataFolder(Param: String): String;
begin
  if IsUninstaller then
    result := ExtractFileDir(ExtractFileDir(ExpandConstant('{uninstallexe}')))
  else
    if (WizardInitialized) and
       (IsTaskSelected('localdir')) then
      result := ExpandConstant('{localappdata}') + '\Programs\{#ApplicationName}'
    else
      result := ExpandConstant('{commonappdata}') + '\Programs\{#ApplicationName}';
end;

Answer 1

您遇到的错误与卸载程序无关；您可以将问题缩小到以下范围：

[Setup]
AppName=My Program
AppVersion=1.5
DefaultDirName=My Program

[Code]
procedure DoSomething;
  external 'DoSomething@{code:GetLibPath}\MyLib.dll stdcall setuponly';

function GetLibPath(Value: string): string;
begin
  Result := 'C:\ValidPathToLib';
end;

从上面的脚本看来，您不能将脚本常量用于导入的 DLL 文件名。甚至延迟加载也无法解决此限制。但是对于您的情况，您可以只使用 {app} 路径，因为您的库实际上就在那里（如果我的意图正确的话）：

...
procedure LoadVCLStyleU(VClStyleFile: string);
  external 'LoadVCLStyleW@{app}\VclStylesInno.dll stdcall uninstallonly';
procedure UnLoadVCLStylesU;
  external 'UnLoadVCLStyles@{app}\VclStylesInno.dll stdcall uninstallonly';
...