Use jenkins agent to set database credentials in web.config during build

Question

Looking for some advice.

Setup:

• Jenkins build agent
• c# .NET 4.5 project
• Oracle database connection string stored in web.config

I'm trying to achieve the following:

1. Store the database username/password as an encrypted key/value pair on Jenkins.
2. Retrieve and pass the username and password to MSBuild which can update web.config with the credentials passed in via the command line.

It's step 2 that I'm having difficulty with and wondered if anyone could help with how to do it?

Thanks!