Passing application's connection string down to a Repository Class Library in ASP.NET 5 using the IConfigurationRoot

Question

I have an ASP.NET 5 MVC Web Application and in Startup.cs I see that the public property

IConfigurationRoot Configuration 

is being set to

Answer 1

A slightly different approach would be to make a static class in your Class Library on which you call a method from the Configure(..)-method in Startup.cs:

public void Configure(IApplicationBuilder app, IHostingEnvironment env)
{
    ...
    ConnectionManager.SetConfig(Configuration);
}

In this case, I've added Configuration as a Singleton in ConfigureServices:

services.AddSingleton(_ => Configuration);

My ConnectionManager looks like this:

public class ConnectionManager
{
    private static IConfiguration currentConfig;

    public static void SetConfig(IConfiguration configuration)
    {
        currentConfig = configuration;
    }

    /// 

    /// Get a connection to the database.
    /// 
    public static SqlConnection GetConnection
    {
        get
        {
            string connectionString = currentConfig.GetConnectionString("MyConnection");
            // Create a new connection for each query.
            SqlConnection connection = new SqlConnection(connectionString);
            return connection;
        }
    }
}

This may or may not have some issues regarding object lifetimes and such, and I'm certainly no fan of static classes but as far as I can tell it's a viable approach. Instead of passing Configuration you could even extract the ConnectionString from the config-file and send only that.