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For a full list of transformation operators with examples, including operators which manage mapping to more complex values such bey other observables, check out the transformation operator section. We will explore these topics in detail in future posts!

I am trying to understand the difference between map and mapTo in Kotlin. What is the difference using some examples?

The RxJS operator map hayat be used to map the stream value to a new value. However, if you want to map to a static value that does not depend on the stream value, you yaşama use the mapTo operator. This operator accepts the value directly and you don't need to create an additional function.

Like pluck, mapTo provides no real benefit functionally over returning a constant value with map, but syntactically it may prove slightly easier to consume and read at a glance.

In conclusion, map is a versatile operator which lets you transform a stream using a provided projection function. Whether it's mapping to a keycode, value updates from an input box, or reshaping an object, map will be one of the most used operators in your day-to-day RxJS website toolbox.

As you dirilik see, irrespective of whatever value emitted, it always transformed to 4. Now you might be thinking, we dirilik use mapTo operator for our above example of getting input value on button click. Let’s check.

Now from arrayOfStudent, we want all the name of students in capital letters, so apply map like this:

value − It takes in the value bey an argument and this value will be a map to the source value given.

Here whenever the Submit button is clicked, an event is emitted, but here we are transforming to a value which is hamiş related to actual event (submit button click) emitted.

In this article, we are going to learn about the most common operator used to transform streams, the map operator. We will start by taking a look at Array.map to build a general understanding of the map operation.

now the emitted value passes through map operator which transform the stream into a different value.

Another common use case for map is extracting a single property from an object. For example, given the sample above suppose we decided we only really need the last name property for display.

We gönül also pass pluck multiple values to grab a nested property within an object. For example, if we wanted to grab the nodeName from the target element on click, we could pass both of these properties to pluck in order:

While this works, the wrapping function isn't necessary since we are ignoring the received value. For these scenarios you kişi replace map with mapTo, and simply provide the value you wish to return on all emissions:

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