How to get first N number of elements from an array

To get the first n elements of an array, use

const slicedArray = array.slice(0, n);

I believe what you're looking for is:

// ...inside the render() function

var size = 3;
var items = list.slice(0, size).map(i => {
    return <myview item={i} key={i.id} />
});                       
return (
  <div>
    {items}
  </div>   
)

arr.length = n

This might be surprising but length property of an array is not only used to get number of array elements but it's also writable and can be used to set array's length MDN link. This will mutate the array.

If you don't care about immutability or don't want to allocate memory i.e. for a game this will be the fastest way.

to empty an array

arr.length = 0

You can filter using index of array.

var months = ['Jan', 'March', 'April', 'June']; months = months.filter((month,idx) => idx < 2) console.log(months);

Use Slice Method

The javascript slice() method returns a portion of an array into a new array object selected from start to end where start and end represent the index of items in that array. The original array will not be modified.

syntax : slice(start, end)

Let us say we have an array with 7 items [5,10,15,20,25,30,35] and we want the first 5 elements from that array:

let array = [5,10,15,20,25,30,35]
let newArray = array.slice(0,5)

console.log(newArray)

Do not try doing that using a map function. Map function should be used to map values from one thing to other. When the number of input and output match.

In this case use filter function which is also available on the array. Filter function is used when you want to selectively take values maching certain criteria. Then you can write your code like

var items = list
             .filter((i, index) => (index < 3))
             .map((i, index) => {
                   return (
                     <myview item={i} key={i.id} />
                   );
              });

The following worked for me.

array.slice( where_to_start_deleting, array.length )

Here is an example

var fruits = ["Banana", "Orange", "Apple", "Mango"];
fruits.slice(2, fruits.length);
//Banana,Orange  ->These first two we get as resultant

Just try this to get first n elements from list:

const slicedList = list.slice(0, n);

Example:

const list = [1,2,3,4,5] console.log(list.slice(0, 3)) // Should return [1,2,3] console.log(list.slice(0, 10)) // Returns [1,2,3,4,5] since this is all we have in 1st 10 elements

Using a simple example:

var letters = ["a", "b", "c", "d"];
var letters_02 = letters.slice(0, 2);
console.log(letters_02)

Output: ["a", "b"]

var letters_12 = letters.slice(1, 2);
console.log(letters_12)

Output: ["b"]

Note: slice provides only a shallow copy and DOES NOT modify the original array.

With lodash, take function, you can achieve this by following:

_.take([1, 2, 3]);
// => [1]
 
_.take([1, 2, 3], 2);
// => [1, 2]
 
_.take([1, 2, 3], 5);
// => [1, 2, 3]
 
_.take([1, 2, 3], 0);
// => []

The slice() method returns a shallow copy of a portion of an array into a new array object selected from start to end (end not included) where start and end represent the index of items in that array. The original array will not be modified.

const animals = ['ant', 'bison', 'camel', 'duck', 'elephant'];

console.log(animals.slice(2));
// expected output: Array ["camel", "duck", "elephant"]

console.log(animals.slice(2, 4));
// expected output: Array ["camel", "duck"]

console.log(animals.slice(1, 5));
// expected output: Array ["bison", "camel", "duck", "elephant"]

console.log(animals.slice(-2));
// expected output: Array ["duck", "elephant"]

console.log(animals.slice(2, -1));
// expected output: Array ["camel", "duck"]

know more

With LInQer you can do:

Enumerable.from(list).take(3).toArray();

Although this question is very old, as for 2021, there is a full implementation of LINQ to object written with the latest feature of ECMAScript (javascript).

The Github repository is: https://github.com/IlanAmoyal/WebPartyLinq

Maybe I'm missing something, but feels like kicking in an open door by suggesting to use splice()? Of course, it's important to remember that this modifies the array.

const myArray = [ 'one', 'two', 'three', 'four', 'five', 'six', 'seven', ] myArray.splice(3) console.log(myArray) // expected output: ['one', 'two', 'three']

It's also possible to grab the elements of the array that are outside of what is being kept:

const myArray = [ 'one', 'two', 'three', 'four', 'five', 'six', 'seven', ] const afterFirstThree = myArray.splice(3) console.log(myArray) // expected output: ['one', 'two', 'three'] console.log(afterFirstThree) // expected output: ['four', 'five', 'six', 'seven'] // if n is larger than myArray.length the entire array is kept and if trying to grab the return, it will be an empty array