por Do you know how to use the method find of JavaScript? Functional programming is a programming style in which we try to use as many functions as possible to execute actions in an efficient and innovative way. In JavaScript, this style also involves the use of methods, which are those functions that belong to a specific object and allow us to modify its elements. In this post, we will teach you how to use the method find JavaScript, one of the methods available to modify arrays.
What is the JavaScript find method?
The method find JavaScript works from definition of a logical proof that is written inside its parentheses. Once this situation is defined, the method will be in charge of finding the first moment in which it is true within the elements of the array statement.
Unlike other methods for manipulating the elements of a arraylike the method map in JavaScript, This JavaScript find method does not return a new array.
Here is an example:
[1, 10, 5, 6].find (val => val > 5)
In the previous line of code we define the logical test val > 5. So, to use the method find from JavaScript we insert the command .find after the array or the name of the array. This method of find JavaScript will go through all the elements of the array to find the first element that passes this test. In our case, The first value greater than five is 10. This will be the value that the method returns to us. As we mentioned before, this method never returns a arraybut a single element.
What happens if, when using the method find of JavaScript, there is no element that passes the logical test? Then, we will get the value undefined as returned result with the find JavaScript:
const arrayNumbers = [16, 25, 158, 31]
const find = arrayNumbers.find (val => val > 1033)
console.log (find)
// expected result: undefined
How to use the JavaScript find method?
In addition to finding numerical values, we can use the method find JavaScript to find different types of values. We can, for example, use it to find a string specific to use the find method.
Suppose we have a array of sports teams. Inside this array, We want to find the team that is playing a game. To do this, we call the properties of the function play that we have created in our post about programming a soccer game in JavaScript.
The easiest thing in this situation with find in JavaScript is to create a function that is responsible for finding the equipment in question using the method find in JavaScript. In general, At we recommend that, whenever you can, you create functions that save the actions to be executed. This will allow you to reuse them later just by calling them by name.
Below we show you an example of how we would create this function. In this example, the array of teams is called ‘teams’, and we call the properties ‘name’ and ‘homeTeamName’ to define the logical test of the find in JavaScript:
udpdateTeams (result)
const homeTeam = this.teams.find(team => team.name === result.homeTeamName)
const awayTeam = this.teams.find(team => team.name === result.awayTeamName)
What the previous function does is search for the method findamong all the teams of the array, the first team whose name is the same as the home team name in the results function. The same happens with the visiting team. Thus, we can also use the method find JavaScript to find type values string.
Whats Next?
Now that you know how to use the method find of JavaScript, We invite you to continue learning with us about all the elements that this programming language offers. To do this, we recommend taking a look at our Full Stack Web Development Bootcamp, an intensive training where you will learn to master this and many other programming languages for the web and concepts such as the find method. What are you waiting for to join? We will wait for you!