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Let's move on to another type
of delegate in C#, Actions.

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Actions are a type of generic delegate
that can be declared at instantiation.

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Remember that generic means that you need
to specify a type when you declare it,

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like we did with lists earlier.

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Actions always return void and
can take multiple parameters.

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How about we look at the documentation
before writing an action?

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We'll type action.net.

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There it is.

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Encapsulates a method that has a single
parameter and does not return a value.

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This specific method signature is
an action that takes a single parameter.

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The T here, in angle brackets,

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represents the type parameter we need
to specify when we declare the action.

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Check out these other versions of
the same method on the left here.

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If you need more than one parameter,

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you'll need to specify each one at
declaration, separated by a comma.

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Let's get back to work spaces.

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We can get rid of our delegate
declaration, SayGreeting.

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Then, we can declare
an action here in main.

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Action, and it'll take a string
parameter inside angle brackets and

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we'll call it, sayGreeting.

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then we can assign our anonymous
method to this say greeting.

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Since we got rid of our delegate
declaration, we'll need to change our

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SayGoodbye functionality to
use another anonymous method.

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I'll do a copy, paste And
I'll change that to Later.

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Now the sayGreeting action is pointing to
different anonymous methods in our program

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and it's a little cleaner than when
we were using the delegate keyword.

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We can get rid of our
sayGoodbye method here.

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Let's see if this works.

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Compile wirh mcs Program.cs and

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mono Program.exe.

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What's your name?

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Carling.

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Hello Carling.

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Yo.

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Later Carling.

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Great, it still works.

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So what if we need a delegate
that returns something?

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Actions don't return anything, that's
where the funk type comes into play.

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The funk type is a delegate that works
like an action, but has a return value.

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Let's take a quick look at
the func documentation, func.net.

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Here it is.

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So with a func, the first
parameter is the in parameter and

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the second one is the out.

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You can see down here, it says in and out.

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If you look at the other ones here on
the left, it's got more methods for

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when you need more than
one input parameter, but

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the output is always
the last type parameter.

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Let's get back to work spaces and we'll
create a func that will write a message to

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the console and
return the input from the user.

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Func and
the type parameters will be string.

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So the in parameter is a string and
the out parameter is a string,

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and we'll call it
conversate = an anonymous

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method delegate string message.

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So, that's our input parameter and

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then we'll write the message
to the console and

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then we'll return whatever the user

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enters Console.ReadLine.

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Okay, we can use this function to get and
store the name.

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So down here, we'll take out string
input and we'll stick it up here.

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So string input = conversate and

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we'll pass it ("what's your name?") and

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then we can get rid of this
("what's your name?") here.

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You see how we're passing in
a string to the sayGreeting action?

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We don't actually have to do that
because the variables we declare

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outside of the function are in the same
scope as the body of the function.

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So we can change its name to input.

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We don't need the name parameter anymore,
but

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we could re-factor this function
to suit both of our greetings.

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We'll change the parameter
to be greeting and

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we can use it for both hello and goodbye.

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And then I'll copy that greeting,
put it here and

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now we can use that for
both saying hello and goodbye.

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So down here instead of input,
you can say Hello, and

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we can get rid of all
of this right here and

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then, Later.

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Let's add some other conversation lines
to make it a little more interesting.

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So conversate, we'll pass,

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("Nice to see you:") and

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then we'll say,

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conversate,("Are you doing well?").

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Now let's run it, and see if it works.

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Mcs Program.cs and

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mono Program.exe.

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What's your name.

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Carling.

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Hello Carling.

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Nice to see you.

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You too.

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Are you doing well?

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Yep.

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Later Carling.

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Awesome.