WiX Read connection string before installation

Question

I'm creating an installer for website. There is a custom dialog for setting up the connection string. After installation it is written to the Web.config. But before the installation user see an empty edit box. Is there any way to read the default connection string from the Web.config from the embedded cab file to show it in the edit box before the installation process?

For now the only solution I see is to write that default value manually. But this way I will have to synchronize it with the content of the Web.config before MSI is created.

Answer 1

If you want to do this at install time, there's no other way than a custom action. If I remember correctly, Community MSI Extensions pack contains something like this.

However, I would do it differently. It sounds like the default value is known at build time. Thus, you can make your build process responsible for placing the same default connection string into the web.config and the MSI property.