In asp.net 1.1 the connectionstring can be extracted using the ConfigurationSettings.AppSettings("KeyName").

In asp.net 2.0 there is a connectionstring section provided in the web.config file. The way to extract this string is to use
Configuration.ConfigurationManager.ConnectionStrings["connstr"].ConnectionString.

One more thing asp.net 2.0 host the web app under development in the asp.net development server and dynamic ports can be assigned. This is different then the way webapps were developed in the asp.net 1.1 which required IIS to be installed on the development machines.