Get connection string in class library project in a solution

In my .net 4 solution, i have two different projects- an web application project and a class library project.

In web application project, database connection string is in web.config file. I would like to access that connection string from class library project. Is it possible? if yes, how?

If there is any better approach to get connection string, please let me know.

Answers:

Thank you for visiting the Q&A section on Magenaut. Please note that all the answers may not help you solve the issue immediately. So please treat them as advisements. If you found the post helpful (or not), leave a comment & I’ll get back to you as soon as possible.

Method 1

To access it from your class library add a reference to System.Configuration then use System.Confinguration.ConfigurationManager.ConnectionStrings.

It’s not ideal to read this from a class library. After all, can you say that your class library will always be consumed by something with a configuration file? Certainly not if you share it with other developers, especially of different platforms.

Consider:

1. IoC – use dependency injection to provide a dependency that contains configuration settings. These would be populated by the consuming library (web app).
2. Pass the settings to the class library when consuming elements that depend on them.

e.g.:

public class MyLibraryContainer
{
    private string _connectionString;

    public MyLibraryContainer(string connectionString)
    {
        _connectionString = connectionString;
    }
}

All methods was sourced from stackoverflow.com or stackexchange.com, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0