In case you need to open a connection manually or just need to know what database you currently working with. 
- Proceed to output folder and open web.config file in text editor. You will find <connectionStrings> section there:
 
<connectionStrings>
<add name="livedemo_northwind_at_localhost" connectionString="Server=localhost;Database=livedemo_northwind;User Id=root;Password=" />
 </connectionStrings>
Notice the name of connection string: "livedemo_northwind_at_localhost"
2. Here is the code that reads connection string and prints it on the page. Replace "livedemo_northwind_at_localhost" with your connection string name. 
System.Configuration.Configuration rootWebConfig =
 System.Web.Configuration.WebConfigurationManager.OpenWebConfiguration("/MyWebSiteRoot"); 
System.Configuration.ConnectionStringSettings connString;
if ( rootWebConfig.ConnectionStrings.ConnectionStrings.Count > 0) {
 connString = rootWebConfig.ConnectionStrings.ConnectionStrings["livedemo_northwind_at_localhost"]; 
 if ( connString != null) {
 MVCFunctions.Echo(connString.ConnectionString);
 }
}