请参考我的问题how to terminate installer if unstallation of legacy version of software is cancelled before executing it?,您可以使用相同的技巧检查注册表检查您的应用是否已安装。
要检查应用程序的版本,您可以使用我从https://blog.lextudio.com/2007/08/inno-setup-script-sample-for-version-comparison-2/ 获得的以下代码:
[Code]
function GetNumber(var temp: String): Integer;
var
part: String;
pos1: Integer;
begin
if Length(temp) = 0 then
begin
Result := -1;
Exit;
end;
pos1 := Pos('.', temp);
if (pos1 = 0) then
begin
Result := StrToInt(temp);
temp := '';
end
else
begin
part := Copy(temp, 1, pos1 - 1);
temp := Copy(temp, pos1 + 1, Length(temp));
Result := StrToInt(part);
end;
end;
function CompareInner(var temp1, temp2: String): Integer;
var
num1, num2: Integer;
begin
num1 := GetNumber(temp1);
num2 := GetNumber(temp2);
if (num1 = -1) or (num2 = -1) then
begin
Result := 0;
Exit;
end;
if (num1 > num2) then
begin
Result := 1;
end
else if (num1 < num2) then
begin
Result := -1;
end
else
begin
Result := CompareInner(temp1, temp2);
end;
end;
function CompareVersion(str1, str2: String): Integer;
var
temp1, temp2: String;
begin
temp1 := str1;
temp2 := str2;
Result := CompareInner(temp1, temp2);
end;
function InitializeSetup(): Boolean;
var
oldVersion: String;
uninstaller: String;
ErrorCode: Integer;
begin
if RegKeyExists(HKEY_LOCAL_MACHINE,'SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\{F768F6BA-F164-4599-BC26-DCCFC2F76855}_is1') then
begin
RegQueryStringValue(HKEY_LOCAL_MACHINE,'SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\{F768F6BA-F164-4599-BC26-DCCFC2F76855}_is1','DisplayVersion', oldVersion);
if (CompareVersion(oldVersion, '6.0.0.1004') < 0) then
begin
if MsgBox('Version ' + oldVersion + ' of Code Beautifier Collection is already installed. Continue to use this old version?',mbConfirmation, MB_YESNO) = IDYES then
begin
Result := False;
end
else
begin
RegQueryStringValue(HKEY_LOCAL_MACHINE,'SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\{F768F6BA-F164-4599-BC26-DCCFC2F76855}_is1','UninstallString', uninstaller);
ShellExec('runas', uninstaller, '/SILENT', '', SW_HIDE, ewWaitUntilTerminated, ErrorCode);
Result := True;
end;
end
else
begin
MsgBox('Version ' + oldVersion + ' of Code Beautifier Collection is already installed. This installer will exit.',mbInformation, MB_OK);
Result := False;
end;
end
else
begin
Result := True;
end;
end;