How to remove duplicate values from array in javascript?

You will learn how to remove duplicate values from an array in javascript. There are many methods but we will teach you the two best and most common methods of removing duplicate values from the array.

1) Remove item from array with filter method.

1let arr = ['apple', 'banana', 'orange', 'mango', 'apple', 'orange'];
2
3    let uniqueValues = arr.filter((value, index) => {
4      return arr.indexOf(value) === index;
5    });
6    console.log(uniqueValues); //["apple", "banana", "orange", "mango"]

In the above example, we have removed duplicate values with the help of the filter method. The indexOf javascript method gets the index of the first appearance of value then we check if it is equal to the current index the return it otherwise skip it.

1) Remove item from array with Set method and spread operator.

1let arr = ['apple', 'banana', 'orange', 'mango', 'apple', 'orange'];
2    const uniqueValues = [...new Set(arr)]
3    console.log(uniqueValues);//["apple", "banana", "orange", "mango"]

The set method removed all duplicate values from the array. This is single line code which removes duplicates.

Related Articles :

• Arrays
• indexOf javascript