for...in
Similar to a for
loop, but used to loop through objects.
var lunch = {
sandwich: 'ham',
snack: 'chips',
drink: 'soda',
desert: 'cookie',
guests: 3,
alcohol: false,
};
for (var key in lunch) {
if (lunch.hasOwnProperty(key)) {
console.log(key); // key
console.log(lunch[key]); // value
}
}
// returns sandwich, ham, snack, chips, drink, soda, desert, cookie, guests, 3, alcohol, false