How to store and retrieve settings from appSettings
This is how you store and retrieve settings in your web.config on Microsoft's .NET 4.0. This also works in Mono. First add a reference in your project to "System.Configuration" Change your web.config like this: <appSettings><add key="ConnectionString" value="server=(local);database=Northwind;Integrated Security=SSPI" /></appSettings> And change your code into this: var connectionString = System.Configuration.ConfigurationManager.AppSettings["ConnectionString"]; using(var connection = new SqlConnection(connectionString)) { connection.Open(); // ... }