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Object.values() - returns an array of a given object’s own enumerable property values ( some older browsers lacking support).Object.keys() - returns an array of a given object’s own enumerable property names ( supported in all browsers).

But first, to convert the object to an Array, you can use one of three methods: The second approach is quite custom and can be divided into a few separate ways. This means that you cannot break the loop, and have to wait when it finishes.īrowser support: Supported in all browsers 2. One of the drawbacks of this method that it will loop over all properties. To check an object’s property enumerable flag you can use the getOwnPropertyDescriptor method.įor ( let property in car ) // Output: // "name: Audi" // "model: A6" // "year: 2012" // "isUsed: true" // "transmission: manual"Īs you can see you have a clear and simple construction inside which you have access to both property name and property value. This means that if the object’s property enumerable flag is set to false, then the loop will not iterate over this property. All of the below approaches will iterate only over enumerable object properties.Įnumerable properties are those properties whose internal enumerable flag is set to true, which is the default for properties created via simple assignment or via a property initializer That said, looping (iterating) through an object can be divided into two main approaches:Ĭonvert the object to an Array and use different methods/loops on itīut before we move on, there’s an important detail to understand. NOTE: in JavaScript, there’s only one built-in way to loop through an object (for…in), all other ways are custom approaches utilizing Arrays. Here is an example that uses the for.There are multiple different ways how to loop through object in JavaScript. This method works in all modern and old browsers including Internet Explorer 6 and higher. The most straightforward way to loop through an object's properties is by using the for.in statement. Methods to loop through objects using javascript for.in Loop Map() will give you TypeError: items.map is not a function: items.map(item => If you have an array that is considered to be an object in javascript, you can’t loop through the array using map(), forEach(), or a for.of loop. Introduction to looping through objects using javascript Methods to loop through objects using javascript.Introduction to undefined and null values in Javascript.