I am using VS2008. I have a project connect with a database and the connection string is read from App.config via ConfigurationManager. We are using L2E.
Now I added a helper project, AndeDataViewer, to have a simple UI to display data from the database for testing/verification purpose.
I don't want to create another set of Entity Data Model in the helper project. I just added all related files as a link in the new helper project.
When I compile, I got the following error:
Error 15 The name 'ConfigurationManager' does not exist in the current context C:\workspace\SystemSoftware\SystemSoftware\src\systeminfo\RuntimeInfo.cs 24 40 AndeDataViewer
In your project, right-click, Add Reference... In the .NET tab, find the "System.Configuration" component name and click OK.
"using System.Configuration" tells the compiler/IntelliSense to search in that namespace for any classes you use. Otherwise you would have to use the full name (System.Configuration.ConfigurationManager) every time. But if you don't add the reference, that namespace/class will not be found anywhere.
Note that a DLL can have any namespace, so the file System.Configuration.dll could in theory have the namespace "Some.Random.Name". For clarity/consistency they're usually the same, but there are exceptions.