Filtering out only null values in JavaScript

Question

Filtering out only null values in JavaScript

JavascriptWeb DevelopmentFront End TechnologyObject Oriented Programming

---

---

We are required to write a JavaScript function that takes in an array that contains some false values. The function should remove all the null values from the array (if there are any) in place.

For example: If the input array is −

const arr = [12, 5, undefined, null, 0, false, null, 67, undefined, false, null];

Then the output should be −

const output = [12, 5, undefined, 0, false, 67, undefined, false];

Example

The code for this will be −

const arr = [12, 5, undefined, null, 0, false, null, 67, undefined,
false, null];
const removeNullValues = arr => {
   for(let i = 0; i < arr.length; ){
      // null's datatype is object and it is a false value
      // so only falsy object that exists in JavaScript is null
      if(typeof arr[i] === 'object' && !arr[i]){
         arr.splice(i, 1);
      }else{
         i++;
         continue;
      };
   };
};
removeNullValues(arr);
console.log(arr);

Output

The output in the console −

[ 12, 5, undefined, 0, false, 67, undefined, false ]

AmitDiwan

Published on 10-Oct-2020 11:32:05

Previous Page Print Page

Next Page  

Advertisements