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So that's classes properties and inheritance with typescript.

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And as I mentioned to these features also generally are supported in JavaScript in modern javascript

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of course with the exception of type assignments and also with the exception of protected private public

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these keywords are really only available in typescript.

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Now it's not all what you can do with classes though when ever need feature which you also have in vanilla

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javascript and which is also supported in typescript R getters and setters.

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Now let's see that here on the accounting department for example let's say there we have a lost report

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property which is a private property and it's of type String.

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So we have that.

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And then here we initialize this to be our reports property or this argument we're getting here and

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there.

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The first value which of course is basically undefined if we pass in an empty reports array.

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Now when we add a report then don't want to set this last report equal to text which is what we add

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to our report's array.

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Now last report is private so we can access it from inside this method.

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But we won't be able to access it from outside with the dot notation.

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Now we can add a getter to still make it accessible a getter is basically a property where you execute

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a function or a method when you retrieve a value.

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And that allows you as a developer to add more complex logic here.

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You create a getter by using to get keyword and then any name of your choice.

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Typically closely related to the property you're trying to control the access to.

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For example here we could name it most recent report.

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Anything like that.

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Now import does is defined like a method.

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So you add parentheses and then curly braces.

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And now in here you have to return something that's important getter method has to return something.

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So here we could return this last report and then we kind of encapsulate this because this is publicly

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accessible now.

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But often you want to have more complex logic here.

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So here we could check if we have a value here.

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So if this is true.

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If it's not undefined then we want to return last report.

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Otherwise you might want to return some different logic.

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For example let's say otherwise we throw an error message with throw in you.

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Error no report found.

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So now we added more logic more complex logic to this property and when we want to retrieve it we can

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directly retrieve his property through the dot notation but we can use this as a property to Deandra

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on this logic.

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So how what does work well down there where I create my accounting department before I add my report

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if I tried to console lock accounting dot most recent report and now important accounting dot most recent

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report and now important You access this as a property so no parentheses here you don't execute does

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as a method you just access it like a normal property.

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And behind the scenes this will execute this method up there.

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So if I tried this now before we added a report we'll see that this rebuilt without errors recompile

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without errors.

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But of course here an error is thrown.

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It's our custom no report found error because no report was added yet.

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And since using this as a getter accesses this method here and executes it if we have no report we don't

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make it into this check we're into this if statement in day out for this line here it kicks in as an

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alternative if we would move that down after we added a report then of course we can save that and we

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no longer get an error but instead we output this last report.

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So that's a getter and you can also add a setter a setter is added almost the same way you used the

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set keyword.

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And then again any name of your choice typically a name related to the property which should be set.

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So here I will reuse most recent report so that we can use this both to read a value and to set a value.

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And then again you defined us like a method.

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But now this needs to take an argument the value which the user would have passed in here.

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This should be a string value.

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And now in here you can run any logic you want to store this.

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Now here since we're passing in a value for the most recent report I in the end want to execute add

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report.

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So here a setter could simply be an alternative to the ADD report method.

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So in here we can access this add report this is required since we're inside of the class.

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We refer to the class and then to this class method here and now we can just forward value here.

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Now we could add a more complex logic and also check if value is maybe not the find if it's false see

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and then just return or throw a new error where we say Please pass in a valid value that is something

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we could also do.

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And now we're using a setter here as well.

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With that added We can test it down there.

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I could add most recent report I could access does on accounting and just like this we would read from

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it.

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But now by adding a equals sign we're trying to set a value to that and that will trigger this setter

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method again just as before we don't execute it as a method but simply access is like a property now

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here if I pass in an empty string then we technically do pass in a string but an empty string will be

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treated as false see here and therefore we should now get an error.

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So if I save this line of code if I save the code with this line of code added we indeed get this error

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please pass it in a valid value.

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If I do pass an invalid value though if I say year end report here for example and I now save this.

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Now you will see this all works and year end report as part of our reports list.

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So these are getters and setters which can be great for encapsulating logic and for adding extra logic

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that should run when you try to read a property or when you try to set a property.