I recently did an internal application deployment to about a dozen users in our IT department, and the application required .NET 2.0. I found that only about 20% of the users had the framework installed on their Windows XP systems, and we had to go out and download .NET for the others.
After that experience, which was a real eye opener, we decided to include a check for the framework in our installation package, and I built a script to automatically download it if it wasn't already installed.
Low user intervention was a key goal, and I suspect that will be the case for most applications. If the user has to jump through a lot of hoops/steps, then they may choose to quit altogether.
I used
InnoSetup for the installer, which is free yet very powerful and certainly a production-quality installer. Here's the script I used that automates the download and installation of the .NET 2.0 Framework prior to installing the application. This would be inside a file with a .iss extension (e.g. installer.iss):
[_ISTool]
EnableISX=true
[Files]
Source: C:\Program Files\ISTool\isxdl.dll; Flags: dontcopy
[Code]
var
dotnetRedistPath: string;
downloadNeeded: boolean;
dotNetNeeded: boolean;
memoDependenciesNeeded: string;
procedure isxdl_AddFile(URL, Filename: PChar);
external 'isxdl_AddFile@files:isxdl.dll stdcall';
function isxdl_DownloadFiles(hWnd: Integer): Integer;
external 'isxdl_DownloadFiles@files:isxdl.dll stdcall';
function isxdl_SetOption(Option, Value: PChar): Integer;
external 'isxdl_SetOption@files:isxdl.dll stdcall';
const
dotnetRedistURL = 'http://download.microsoft.com/download/5/6/7/567758a3-759e-473e-bf8f-52154438565a/dotnetfx.exe';
// local system for testing...
// dotnetRedistURL = 'http://192.168.1.1/dotnetfx.exe';
function InitializeSetup(): Boolean;
begin
Result := true;
dotNetNeeded := false;
// Check for required netfx installation
if (not RegKeyExists(HKLM, 'Software\Microsoft\.NETFramework\policy\v2.0')) then begin
dotNetNeeded := true;
if (not IsAdminLoggedOn()) then begin
MsgBox('This application needs the Microsoft .NET Framework to be installed by an Administrator', mbInformation, MB_OK);
Result := false;
end else begin
memoDependenciesNeeded := memoDependenciesNeeded + ' .NET Framework' #13;
dotnetRedistPath := ExpandConstant('{src}\dotnetfx.exe');
if not FileExists(dotnetRedistPath) then begin
dotnetRedistPath := ExpandConstant('{tmp}\dotnetfx.exe');
if not FileExists(dotnetRedistPath) then begin
isxdl_AddFile(dotnetRedistURL, dotnetRedistPath);
downloadNeeded := true;
end;
end;
SetIniString('install', 'dotnetRedist', dotnetRedistPath, ExpandConstant('{tmp}\dep.ini'));
end;
end;
end;
function NextButtonClick(CurPage: Integer): Boolean;
var
hWnd: Integer;
ResultCode: Integer;
begin
Result := true;
if CurPage = wpReady then begin
hWnd := StrToInt(ExpandConstant('{wizardhwnd}'));
// don't try to init isxdl if it's not needed because it will error on < ie 3
if downloadNeeded then begin
isxdl_SetOption('label', 'Downloading Microsoft .NET Framework');
isxdl_SetOption('description', 'This application needs to install the Microsoft .NET Framework. Please wait while Setup is downloading extra files to your computer.');
if isxdl_DownloadFiles(hWnd) = 0 then Result := false;
end;
if (Result = true) and (dotNetNeeded = true) then begin
if Exec(ExpandConstant(dotnetRedistPath), '', '', SW_SHOW, ewWaitUntilTerminated, ResultCode) then begin
// handle success if necessary; ResultCode contains the exit code
if not (ResultCode = 0) then begin
Result := false;
end;
end else begin
// handle failure if necessary; ResultCode contains the error code
Result := false;
end;
end;
end;
end;
function UpdateReadyMemo(Space, NewLine, MemoUserInfoInfo, MemoDirInfo, MemoTypeInfo, MemoComponentsInfo, MemoGroupInfo, MemoTasksInfo: String): String;
var
s: string;
begin
if memoDependenciesNeeded <> '' then s := s + 'Dependencies to install:' + NewLine + memoDependenciesNeeded + NewLine;
s := s + MemoDirInfo + NewLine + NewLine;
Result := s
end;
