C# Coding - Delegate and Event Setup

[ama_trig]

Class A
{
	
	ButtonClick()
	{
		//SomeVariable
		//SomeCode

		***According to SomeVariable, set callback of Class B's Method_1 to
		*** UpdataA Method or UpdateB Method or anything else defined here 
		***(not written in Method_1 code block, so it can be changed from here)
			Something like this :
			Call ClassB.Method2(timer_interval,Method_UpdateA_ResultOfMethod1)
			or 
			Call ClassB.Method2(timer_interval,Method_UpdateA_ResultOfMethod2)
	}

	Method_UpdateA_ResultOfMethod1(string INPUT)
	{
		//some code
		//Display Input
	}

	Method_UpdateB_ResultOfMethod1(string INPUT)
	{
		//some code
		//Display Input
	}
}

Class B
{
	Method_1()
	{
		//some code
		How to callback to Class A method (predefined by method 2) and pass an argument?
	}
	
	Method_2(?)
	{
		//Install Timer On method 1 that triggers every second
		How to set a callback to One of methods of Class A ?
	}
}

No matter how much I try, I couldn't make it work, it seems fairly easy in c using function pointer, but in c# I'm stock.
So far what I've read is that an event and delegate must be used, But I couldn't make it work, I think this is because I don't understand anonymous delegates, event, ... well enough.