How to efficiently count the number of keys/properties of an object in JavaScript

How to efficiently count the number of keys/properties of an object in JavaScript

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Dynamically access object property using variable

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Sorting object property by values

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Test for existence of nested JavaScript object key

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How do I enumerate the properties of a JavaScript object? [duplicate]

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How to use a variable for a key in a JavaScript object literal?

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What is the difference between properties and attributes in HTML?

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How to create an object property from a variable value in JavaScript? [duplicate]

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react-router - pass props to handler component

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Remove array element based on object property

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Can I update a component's props in React.js?

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Is there a “not in” operator in JavaScript for checking object properties?

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Getting the object's property name

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Why does 2 == [2] in JavaScript?

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How do I reference a JavaScript object property with a hyphen in it?

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