Inno Setup做更新包
When deploying an installation that is an "update" (or "add-on") to an existing installation, you probably want the following criteria to be met:
The update must be installed to the same directory as the original application.
Any new files installed by the update must be removed when the original application is uninstalled.
The update should not create a new entry in the Add/Remove Programs list, or alter the original application's entry. Nor should the application name displayed by the uninstaller change.
1 and 2 may be achieved by giving your update installation the same AppId setting as the original application. (If you never set AppId in the original application, then set AppId to the value of AppName used in the original application.) This, when combined with UsePreviousAppDir=yes (the default setting), will cause the update installation to default to the same directory as the original application, and share the same uninstall log file (unins???.dat).
3 may be achieved by setting CreateUninstallRegKey=no and UpdateUninstallLogAppName=no.
