Below is an example of a Singleton implementation C# class.
public sealed class StaticData
{
private StaticData() {}
public static readonly StaticData Instance = new StaticData();
string connectionString = "";
public string ConnectionToUse
{
get
{
if (connectionString.Length == 0)
{
connectionString = System.Configuration.ConfigurationManager.AppSettings.Get("DBConnection").ToString();
}
return connectionString;
}
}
}