Blog

To get multiple random elements from an array in JavaScript, you can use the following approach:

1. Use the Array.slice() method or spread operator to create a copy of the array.
2. Use the Array.sort() method to sort the array in a random order.
3. Use the Array.slice() method to select the desired number of elements from the sorted array.

Let’s discuss this in detail below.

Get Multiple Random Elements From An Array In JavaScript

We can use the Array.slice() method or spread operator to create a copy of the array, and then use the Array.sort() method to sort the array in a random order. Finally, we can use the Array.slice() method to select the desired number of elements from the sorted array:

const arr = [‘a’, ‘b’, ‘c’, ‘d’, ‘e’, ‘f’, ‘g’, ‘h’];

const copy = arr.slice();

copy.sort(() => Math.random() – 0.5);

console.log(copy.slice(0, 4));

// [‘a’, ‘c’, ‘e’, ‘h’]

In the above code, we first created a copy of the array using the Array.slice() method. We then used the Array.sort() method to sort the array in a random order.

Math.random() method is used to get a pseudorandom number between 0 and 1, and subtracting 0.5 from it gives us a pseudorandom number between -0.5 and 0.5.

When we sort the array with these values, the order of the elements in the array is randomized.

Finally, we used the Array.slice() method to select the desired number of elements from the sorted array.

The Array.slice() method takes two arguments, the first argument is the index of the element where the slicing should start, and the second argument is the index of the element where the slicing should end (the element at this index is not included in the sliced array).

In our case, we have used 0 as the first argument and 4 as the second argument, so we are only selecting the first 4 elements from the array.

This approach can be used to get multiple random elements from an array of any type, including strings, numbers, and objects.

Note: The Array.slice() method creates a shallow copy of the array, meaning that the original array is not modified.

We can also use the spread operator to create a copy of the array:

const arr = [‘a’, ‘b’, ‘c’, ‘d’, ‘e’, ‘f’, ‘g’, ‘h’];

const copy =

[...arr].sort(() => Math.random() – 0.5);

console.log(copy.slice(0, 4));

// [‘a’, ‘c’, ‘e’, ‘h’]

In the above code, we have used the spread operator to create a copy of the array, and then used the Array.sort() method and Array.slice() method to get multiple random elements from the array.

We can also use the for loop to get multiple random elements from an array:

const arr = [‘a’, ‘b’, ‘c’, ‘d’, ‘e’, ‘f’, ‘g’, ‘h’];

const copy = [];

for(let i=0; i < 4; i++){

  const index = Math.floor(Math.random() * arr.length);

  copy.push(arr.splice(index, 1)[0]);

}

console.log(copy);

// [‘a’, ‘c’, ‘e’, ‘h’]

In the above code, we have used the for loop to get multiple random elements from the array.

First, we created an empty array named copy.

Then, we used the for loop to iterate 4 times. In each iteration, we generated a random index using the Math.random() method and Math.floor() method.

The Math.floor() method rounds a number down to the nearest integer.

Next, we used the Array.splice() method to remove the element at the generated index from the original array and add it to the copy array.

The Array.splice() method takes two arguments, the first argument is the index of the element where the splicing should start, and the second argument is the number of elements to be removed. In our case, we have used 1 as the second argument, so only one element is removed from the array.

The Array.splice() method returns an array containing the removed elements.

Since we are only interested in the removed element, we have used arr.splice(index, 1)[0] to get the element and push it into the copy array.

This approach can be used to get multiple random elements from an array of any type, including strings, numbers, and objects.

Conclusion

In this article, we have learned how to get multiple random elements from an array in JavaScript. There are many ways to do this, and the approach that you choose should be based on your requirements.

If you have any questions or feedback, feel free to leave a comment.