how to ignore files in kiln/mercurial using tortoise hg "that are part of the repository"

We use tortoise hg with Kiln. In my vs 2010 c# project there are some files that are part of the repository but I would like tortoise hg to ignore them when I make a commit. For eg., say in a login screen I may hard code the userid, password for testing. I dont really want this file considered during a commit. I understand .hgignore file but this really works for files that are not part of the repo. Any trick in tortoise hg to ignore files that are part of the repo ? (so they do not show up as modified (M) during a commit.) thanks

I always use a combination of .hgignore and BeforeBuild (in the .csproj file) for things like this.

In one of my pet projects, I have the following setup:

App.config contains my real hardcoded user id and password for testing.
App.config.example is identical, but with fake data like "dummy_user" and "dummy_pw".

App.config is not part of the repository, and it's ignored (in .hgignore).
App.config.example is part of the repository.

Then, I have the following in the BeforeBuild target in the .csproj file of my solution:

<Target Name="BeforeBuild">
  <Copy
    Condition="!Exists('App.config')"
    SourceFiles="App.config.example" 
    DestinationFiles="App.config"/>
</Target>

All this together has the following effect:

• the config file with the real data can never be accidentally committed to the repository, because it's ignored
• the repository only contains the config file with the example data
• if someone else clones the repository to his machine, he won't have the "real" config file...but if it's missing, it will be automatically created before the first build by Visual Studio / MSBuild by simply copying the .example file (and then he can just put his real login data into the newly created App.config file).
• if an App.config with real hardcoded user data already exists, it won't be overwritten when building because the BeforeBuild event will only happen if App.config does not already exist