Using Objects in For Of Loops

Question

Why isn\'t is possible to use objects in for of loops? Or is this a browser bug? This code doesn\'t work in Chrome 42, saying undefined is not a function:

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Answer 1

If you are storing data in a key-value store, please use Map which is explicitly designed for this purpose.

If you have to use an object though, ES2017 (ES8) allows you to use Object.values:

const foo = { a: 'foo', z: 'bar', m: 'baz' };
for (let value of Object.values(foo)) {
    console.log(value);
}

If that isn't supported yet, use a polyfill: Alternative version for Object.values()

And finally if you're supporting an older environment that don't support this syntax, you'll have to resort to using forEach and Object.keys:

var obj = { a: 'foo', z: 'bar', m: 'baz' };
Object.keys(obj).forEach(function (prop) {
    var value = obj[prop];
    console.log(value);
});