Sep 06, 2010
In C# Langaugage, Microsoft has provided the facility of multi-cast delegate to implement the Observer Pattern. As Rajesh has mentioned there are sites which provides the implementation of same.
At the same time there is something you need to be aware off when using the multi-cast delegate. If the user has assigned, say two delegates and then assigns a null value, it will be treated as un-assigned and both previously assigned delegates will not execute.