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In this lecture, we are going to explore a creation operator for creating observables out of events.

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It's highly likely you will need to work with DOM events.

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The from event operator will create an observable from an event.

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Let's try using these from event operator on the import statement.

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Swap the interval operator with the from event operator.

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Next, we need to perform the same swap for the variable.

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The from event operator has two arguments.

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The first argument is the targets the target refers to the elements in the document the observable should

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watch.

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We're going to keep this example simple.

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We will listen for events on the document object.

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The second argument is the name of the event.

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Every event in JavaScript is supported.

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Let's listen for a click event.

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On the page, we can click on the document to Imette, the event.

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The observer will receive the event object with every click by using the from event operator.

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We can create an observable out of an event.

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Each subscription will be given its own handler every time we call the subscribed function.

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A new event listener is created for each subscription.

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This behavior allows for other subscriptions to remain functional and uninterrupted.

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The operator will handle this process for us as usual.

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The observable will listen for clicky events until the user closes the app.

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If we don't need to listen for events, we should unsubscribe from the observable.

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Otherwise, we may experience a memory leak.

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The from event operator will not automatically stop listening for events in a future lecture.

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We will explore how to complete an observable with operators.

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For now, we must manually unsubscribe from an observable with the unsubscribe function in the next

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lecture.

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We are going to explore some more creation operators.