Introduction to JavaScript: First Steps/

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for-in loops

for-in loops

The for-in loop is specifically designed to work with objects. Learn how to loop through an object's keys in order to process each of them.

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We’ve seen that for-loops are great for looping through arrays. There’s another type of loop for objects, the for-in loop.

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let jon = {
    firstName: 'Jon',
    lastName: 'Smith',
    age: 34,
    profession: 'Developer',
    married: true
};
for(let key in jon) {
    console.log(key, ':', jon[key]);
}

We start it out as a standard for-loop.

for() {
		// body
}
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