array_to_object.js

const array = [
  [ 'one', 1 ],
  [ 'two', 2 ]
];

Object.fromEntries(array);
// { one: 1, two: 2 }

object_to_array1.js

const zoo = {
  lion: '🦁',
  panda: '🐼'
};

Object.keys(zoo)
// ['lion', 'panda']

Object.values(zoo)
// ['🦁', '🐼']

Object.entries(zoo)
// [ ['lion', '🦁'], ['panda', '🐼'] ]

object_to_array2.js

var numbers = {
  one: 1,
  two: 2
};

var keys = [];

for (var number in numbers) {
  if(numbers.hasOwnProperty(number)){
    keys.push(number)
  }
}

keys; // [ 'one', 'two' ]

Object.keys(numbers);
// [ 'one', 'two' ]

Object.values(numbers);
// [ 1, 2 ]

Object.entries(numbers);
// [ ['one', 1], ['two', 2] ]

object_to_array3.js

const numbers = {
  one: 1,
}

const objectArray = Object.entries(numbers);

objectArray.forEach(([key, value]) => {
  console.log(key); // 'one'
  console.log(value); // 1
})