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And now our nice feature related to properties and methods which exists also in JavaScript when you're

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using iOS 6 or later but also typescript are static properties and methods static properties and methods

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allow you to add properties and methods to classes which are not accessed on an instance of the class

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so where you don't need to call new class name first but once you access directly on the class this

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is often used for utility functions that you want to group or map to a class logically or global constants

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which you also want to store in a class.

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An example built into javascript which is not defined by TypeScript and not defined by you but part

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of JavaScript in the browser is the math constructor function or a class if you want to call it like

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this that's globally available in JavaScript where you can access pi as a constant value to give you

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that pi number or functions or methods to be precise like p o w to calculate the power of something.

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These are methods on properties which you don't access on the instance of math you don't have to call

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new math first.

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Indeed that won't work but you access these properties and methods directly on the class itself.

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So moth acts more like a namespace as a grouping mechanism here and that's a common use case for static

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methods and properties and you can add them to your own classes as well let's say on department we want

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to have the method that helps us create employees and dad is something we might want to be able to access

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without instantiating department because we typically instantiate our more specialized versions I.T.

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department and accounting department and we don't really want to instantiate department just to call

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a utility method and therefore we can Adam effort here create employee let's say where we want to get

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the name which is a string as an argument and there we want to return something now to make that a static

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method which we can access without instantiating this class we add the static keyword in front of this

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method and then in here we maybe return an object where we have the Name property mapped to this name

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value.

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Now of course that's a very simple method but you get the idea now to use that we could go down there

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where we execute our code and now let's say we want a new employee employee 1 well then we can just

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get this with the part meant dot create employee and pass and Max for example and if I then console

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log employee 1 we should see an object with a name of Max.

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So if I save that indeed here there's this deep employee we just created.

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So this would be a typical example for a static method we call it directly on the class without the

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new keyword and therefore we use the class as a grouping mechanism you could say and if you would want

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to add a static property you could do that as well if you had something like the fiscal year here that

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you currently want to use in your company.

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You could set this to let's say 2020.

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And then again to make it available without instantiating this you could add static in front of this

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property or in front of that field and now X is dead.

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So now down there.

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Right console log my created employee here.

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We can also access Department DOD fiscal year.

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Just like that without instantiating it.

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And if we save that unsurprisingly we'll see 2020 being locked here.

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So these are static methods and properties.

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One important word about them or one thing you should keep in mind when you add them on a class you

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can't access them from inside your non static parts.

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So if you feel like accessing the fiscal year in the clear in the constructor and you want a console

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log it here this as you can see will not work.

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I'm getting an error here that the property fiscal year is a static member we can't access this here

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because the constructor and basically anything in there all the methods as well which are not marked

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with static and you can't mark de constructor s static by the way will not be able to access static

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properties because this does refer to the instance created based on the class.

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Well the static property is not a way to block the instance because the whole idea behind static properties

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and static methods is that they're detached from instances.

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So of course you can't access them with the this keyword if you would want to use the static property

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or a method from inside the class.

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You would have to use to class name here to access it.

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This gives you access to static properties and methods.

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Also from inside the CLOs that's one important thing to keep in mind.