Double-Checked Locking:?

• This is a more advanced form of lazy initialization that avoids the performance

overhead of locking once the instance has been created.

public class Singleton
{
private static Singleton _instance;
private static readonly object _lock = new object();
private Singleton() { }
public static Singleton Instance
{

get

{
if (_instance == null)
{

lock (_lock)

{
if (_instance == null)
{
_instance = new Singleton();
}
}
}
return _instance;
}
}
}