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Now, let's focus two more concepts nested class and in a class, and we're going to need them later

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on.

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So let's look at the concepts here.

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A class which is created inside another class and a class which is created inside another class with

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the key word inner.

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So this is the difference between the two, but there are a little more differences that we need to

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look at.

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So let's look at the master class.

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First in the class is such a class which is created inside another class in Scotland.

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An asset class is by default static.

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So its data members and no functions can be accessed without creating an object of the class.

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So without having to create an object of this nested class, you can go ahead and use the functions

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and members.

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Then the asset class cannot access data on members of the outer class, so it's a one way relationship.

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So only the poorer class can access the members of the master class, but not the other way around.

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So let's look at this we have a class called our class, and then inside of this class we create another

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class called master class.

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OK.

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And usually you should create classes which are separated so each having their own file.

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But sometimes it just makes sense to have a nested class.

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For example, if you really just need it's functionality within the upper class that we're using here,

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and this is class example that we see here is that we have this other class and there we have a variable

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called name.

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And it said that to Mr. X.

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And then we have this business class, which has a description, and then it has an ID, which is of

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type and at a function called Foom, which just prints the name and the ID.

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And then we go to our main function where we try to access the description.

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So in order to access the description, we go to our outer class and then inside of that, we go to

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the nascita.

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So we're accessing the property here, and then we create an object of the asset class and we access

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the function.

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So the function of that master class.

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So the output is code inside the NSA class and it is one on one.

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So now let's look at the inner class concept, and in a class is a class which is created inside another

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class with the keyboard inner.

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In other words, we can say that the NSA class, which is marked as inner, is called an inner class.

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So it's still an asset class, but it has this additional keyword, right?

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But the difference now is and in a class cannot be declared inside interfaces or in asset classes.

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And the advantage of in our classes is that they are able to access members of its outer class even

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though they are private.

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So this is a huge difference, right?

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So the inner class keeps a reference to an object of its outer class.

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So if you look at this example here, this is the syntax of an inner class.

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So we have the upper class and we have dismissed the class, but we add the inner keyword.

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So in there just before the class keyword?

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All right.

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And then if we look at this example that we had before.

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The only difference now is that we add in a keyword here to our in a class and that we now can access

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name and ID.

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We could, of course, beforehand access the idea anyways, but we couldn't access the name.

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So you can see here the name that we're using is from the outer class.

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So here where we have this private keyword, even so, we say, OK, this is private, so it should

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only be available within this class.

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But with the inner classes, you actually have access to even private class members of your class.

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OK, so that's the huge difference in an asset class without this inner keyword.

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This wouldn't be possible.

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So sometimes it just makes sense, and sometimes you just need this functionality and then you make

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it into the class and you can use it.

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So going back to our function mean here we have our outer class in our class description so we can access

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the property as we did before and can also access the object form.

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So we'll create an object of that in our class, which is inside of our outer class, and then we can

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go ahead and use its member functions.

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So the output here is code inside in a class name is Mr. X, and it's one one.

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So we didn't have this name is Mr. X before.

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All right, so that's it for now.

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Let's get back to ccording, where we are actually going to use this functionality and then we'll make

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a lot more sense because it's a little bit abstract to look at it that way.

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So let's get into coding.