No need to make this complicated. Just figure out your connection string like you did you original variable.

public class Program// note the class name, here

{

public static string MyVariable { get; set; }// this is the public-scoped variable

public static string ConnectionString { get; set; }

static void Main(string[] args)

{

if (args.Length != 0)

{

MyVariable = "Test";

ConnectionString = ConfigurationManager.ConnectionStrings["Conn2"].ConnectionString;

}

else

{

ConnectionString = ConfigurationManager.ConnectionStrings["Conn1"].ConnectionString;

}

var theForm = new Form1();

Application.Run(theForm);

}

}

Then just change your code slightly to use the static string each time you make a new connection instead of reading from the config.