JSFiddle - React, Tailwind, and code Playground

by anonystick

JavaScript

// không dùng filter
function bouncerWithoutFilter(arr) {
// Don't show a false ID to this bouncer.

    var falsy;
    var trueArr = [];

    for (i = 0; i < arr.length; i++) {

        falsy =  Boolean(arr[i]);

        if (falsy === true) {

        trueArr.push(arr[i]);

        }

    }

    return trueArr;
}

console.log(bouncerWithoutFilter([7, "ate", "", false, undefined, null, 9]))

// dùng filter
function bouncerWithFilter(arr) {
 return arr.filter(element => Boolean(element) === true)
  //or
  //return arr.filter(element => element)
  //or
  
  return arr.filter(Boolean)
}

console.log(bouncerWithFilter([7, "ate", "", false, undefined, null, 9]))

someArray = [{name: 'Jon Snow', age: '20'}, undefined, 400, null, 'from Winterfell',,,'',, null];

console.log(someArray.filter(Boolean))