LINQ 2 SQL: Partial Classes

I need to set ConnectionString for my AppSetting based DataContext. I am trying to do this by creating a Partial Class for each DataContext. Below is what I have so far and I am wondering if I am missing something?

In particular, am I using my DataContext correctly (recycling, persistence, etc.)?

Doing this will I have problems with updates and inserts? Is the file BLLAspnetdb.cs

useful or necessary at least, or should it all be in the generated file partial class AspnetdbDataContext

?

In short, is this an acceptable framework, or will it cause me problems when I design it?

dbml File name = Aspnetdb.dbml

File name Partial class = Aspnetdb.cs

partial class AspnetdbDataContext
{
    public static bool IsDisconnectedUser
    {
        get
        {
            return Convert.ToBoolean(ConfigurationManager.AppSettings["IsDisconnectedUser"]) == true;
        }
    }
    public static AspnetdbDataContext New
    {
        get
        {
            var cs = IsDisconnectedUser ? Settings.Default.Central_aspnetdbConnectionString : Settings.Default.aspnetdbConnectionString;
            return new AspnetdbDataContext(cs);
        }
    }
}

      

        
        
        
      

    

My generated file name = BLLAspnetdb.cs

public class BLLAspnetdb
{
    public static IList WorkerList(Guid userID)
    {
        var DB = AspnetdbDataContext.New;
        var workers = from user in DB.tblDemographics
                          where user.UserID == userID
                          select new { user.FirstName, user.LastName, user.Phone };

        IList theWorkers = workers.ToList();

        return theWorkers;
    }

    public static String NurseName(Guid? userID)
    {
        var DB = AspnetdbDataContext.New;

        var nurseName = from demographic in DB.tblDemographics
                        where demographic.UserID == userID
                        select demographic.FirstName +" " + demographic.LastName;

        return nurseName.SingleOrDefault();
    }

    public static String SocialWorkerName(Guid? userID)
    {
        var DB = AspnetdbDataContext.New;

        var swName = from demographic in DB.tblDemographics
                        where demographic.UserID == userID
                        select demographic.FirstName + " " + demographic.LastName;

        return swName.SingleOrDefault();
    }
}

      

        
        
        
      

    

see this previous question and accepted answer for background on how I got here ... switch-connectionstrings-between-local-and-remote-with-linq-to-sql