How to force Inno Setup to set the installation folder dynamically

Question

I am creating an installation package and user should be able to install it on a specific location only.

In order to do so I read some registry values in the

Answer 1

• Use a scripted constant to set the default installation path;
• Use the DisableDirPage directive to prevent an user from modifying it.

[Setup]
DefaultDirName={code:GetDefaultDirName}
DisableDirPage=Yes

[Code]

function GetDefaultDirName(Param: string): string;
begin
  Result := ...;
end;