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‫Now.

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‫Did you know the theory of methods?

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‫Let's have a look at the practical aspect of methods.

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‫So let's create a method and we start off by an access modifier and I'm just going to use public.

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‫Then I add the return type, which is void, and then I give a name.

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‫In my case I'm just going to call that write something.

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‫So this method is going to write something.

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‫And first of all, I start like that.

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‫I need curly brackets and in here I simply want to use the console right line.

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‫So I'm just going to write something onto the console.

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‫And this is going to be I am called from a method so pretty simple and then console but read so nothing

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‫too fancy yet and nothing that we haven't seen yet except for this being inside of a method.

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‫So now in order to call this method and to run it, we need to call it within the main method.

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‫So this method here is a method itself and this method is not public, so it doesn't have an access

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‫modifier.

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‫I could even get rid of this access modifier, so I could simply say Void, write something, but we'll

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‫get into the different access modifiers later on.

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‫So this one doesn't have one or main method because it should only be called from this class itself.

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‫Then we have void, which means that this method is never going to return anything.

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‫And then the name is called Main and because well, it's pretty much our main method, it's the, the

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‫one that is really important.

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‫And then within the parentheses you have an array of strings which is called ARX, and that's something

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‫that we will cover later on.

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‫So we haven't seen what arrays are, but we will do so later and you will see what ARGs are as well.

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‫So this is our method and here is our starting point as you have read in the last video or have seen

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‫in the last video.

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‫So whatever we want to run, we need to start it from here.

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‫So let's start and call our write something method.

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‫Now we do get an error here.

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‫We cannot simply call our write something method within the main method because our main method is static.

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‫And that's why the write something method has to be static as well.

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‫So I add the static term and as you can see, it's between the access modifier and the return type.

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‫All right.

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‫So.

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‫Axis modifier, then static, then return type.

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‫And then name of the method or method name.

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‫All right, so that's the order.

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‫And then afterwards, in parentheses, you have parameter one and parameter two, and they have to be

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‫separated by a comma.

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‫All right.

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‫So that's the usual structure and that's what we have here.

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‫So we have a public, which is the excess modifier.

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‫We have static, which is used because the main method is static.

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‫And static simply means that this method is static and declares a static member which belongs to the

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‫type itself rather than to a specific object.

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‫That's also something that will make a lot more sense as soon as we get to the point where we use object

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‫oriented programming.

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‫So for now, just know that whenever you want to call a method within a static method, you need to

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‫make the method itself static as well.

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‫So for now, as we don't use object oriented programming and the whole, the bigger concepts would rather

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‫be difficult to understand.

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‫Just let's just keep it at that.

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‫Because static is required here, because we want to call it from another static method.

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‫All right.

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‫And later on, if we have multiple classes, that will not be required anymore, and then we'll have

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‫a look at that as well.

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‫So here's our result.

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‫I am called from a method.

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‫So as you can see, we didn't have to write it within our main method.

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‫We simply wrote it in here.

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‫So you can create very long methods which do loads of things, and then you can simply call them in

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‫one line.

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‫So this is how we call them and that's how we declare or create them.

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‫And a method should usually do one thing.

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‫So in this case, this method is just there to write something.

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‫So you shouldn't create methods which do 20 different things or something like that.

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‫It's best if you keep it simple.

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‫So if you want to have a method which does something else, then create an additional method.

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‫So a separate method.

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‫All right, so let's create an additional method which doesn't just write something what we have here,

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‫but which writes something that we want to have.

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‫So public static void, write something specific.

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‫So our first example, it just wrote anything.

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‫Well, whatever was written in here.

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‫But now what I want to have, I want to declare what I want to write whenever I call this method.

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‫So let's have a look at that.

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‫So I'm going to use console right line and now what should I write here?

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‫So I don't want to write anything.

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‫I want to write something specific.

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‫And what that is, is what I'm going to add as a parameter.

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‫So here I have parameter one and parameter two, and in here I want to have only one parameter, which

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‫is going to be the text of type string.

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‫So my text is going to be the parameter and whenever I want to call this method, I can now hand over

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‫my text and it will be printed onto the console.

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‫So I deliver my text here and now it will write to the console.

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‫So let's create read as well or call the read method here as well in order to write it onto the console.

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‫And now let's call this write something specific method.

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‫And if we just call it like that, we get an error because it says there is no argument given that corresponds

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‫to the required formal power parameter.

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‫My text.

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‫So that means we need to give an argument.

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‫All right.

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‫So when you create a method, this is called parameter.

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‫But when you call the method, what you hand over is the argument.

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‫So I'm going to hand over the argument.

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‫I am an argument and am called from a method.

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‫And here, as you can see, I use exclamation marks as well because this is of type string.

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‫So my text is of type string, so I have to hand over a string here.

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‫So let's run that as well.

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‫And you might wonder I am called from a method is shown, but I am an argument and I'm called from a

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‫method is not written onto our console.

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‫Why is that.

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‫That has to do with this, right?

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‫Because console read reads out whatever is written by that point and it doesn't read whatever is written

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‫afterwards.

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‫So what we can do is get rid of that console right from here and simply call it in here.

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‫So.

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‫Console dot read.

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‫And now let's try it again.

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‫And as you can see, I'm called from a method and I am another argument and I'm called from a method.

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‫So you have seen how to use arguments and parameters and create methods and use void.

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‫And we're going to have a look at other types as well.

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‫So in the next video, we're going to have a look at different return types.

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‫And then we're also going to use more than just one parameter.