62 lines
1.8 KiB
Plaintext
62 lines
1.8 KiB
Plaintext
// The following code taken from https://stackoverflow.com/questions/2000296/innosetup-how-to-automatically-uninstall-previous-installed-version
|
|
// It performs upgrades by running the uninstaller before the install
|
|
|
|
/////////////////////////////////////////////////////////////////////
|
|
function GetUninstallString(): String;
|
|
var
|
|
sUnInstPath: String;
|
|
sUnInstallString: String;
|
|
begin
|
|
sUnInstPath := ExpandConstant('Software\Microsoft\Windows\CurrentVersion\Uninstall\Rust_is1');
|
|
sUnInstallString := '';
|
|
if not RegQueryStringValue(HKLM, sUnInstPath, 'UninstallString', sUnInstallString) then
|
|
RegQueryStringValue(HKCU, sUnInstPath, 'UninstallString', sUnInstallString);
|
|
Result := sUnInstallString;
|
|
end;
|
|
|
|
|
|
/////////////////////////////////////////////////////////////////////
|
|
function IsUpgrade(): Boolean;
|
|
begin
|
|
Result := (GetUninstallString() <> '');
|
|
end;
|
|
|
|
|
|
/////////////////////////////////////////////////////////////////////
|
|
function UnInstallOldVersion(): Integer;
|
|
var
|
|
sUnInstallString: String;
|
|
iResultCode: Integer;
|
|
begin
|
|
// Return Values:
|
|
// 1 - uninstall string is empty
|
|
// 2 - error executing the UnInstallString
|
|
// 3 - successfully executed the UnInstallString
|
|
|
|
// default return value
|
|
Result := 0;
|
|
|
|
// get the uninstall string of the old app
|
|
sUnInstallString := GetUninstallString();
|
|
if sUnInstallString <> '' then begin
|
|
sUnInstallString := RemoveQuotes(sUnInstallString);
|
|
if Exec(sUnInstallString, '/SILENT /NORESTART /SUPPRESSMSGBOXES','', SW_HIDE, ewWaitUntilTerminated, iResultCode) then
|
|
Result := 3
|
|
else
|
|
Result := 2;
|
|
end else
|
|
Result := 1;
|
|
end;
|
|
|
|
/////////////////////////////////////////////////////////////////////
|
|
procedure UpgradeCurStepChanged(CurStep: TSetupStep);
|
|
begin
|
|
if (CurStep=ssInstall) then
|
|
begin
|
|
if (IsUpgrade()) then
|
|
begin
|
|
UnInstallOldVersion();
|
|
end;
|
|
end;
|
|
end;
|