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You have seen 3 ways to iterate over an array of objects. Now, you can check the objects and remove items from the array very easily. I am creating the loop over the people array and getting each object in the person variable. This method accepts a callback function and executes that function for each item in the array. The forEach() method is one of the easiest ways to iterate over an array of objects. Use forEach() to Loop Over an Array of Objects You will also learn when you should choose which one at the end of the post. You will see 3 ways to loop over this array of objects. I will use this " people" array to give you examples though out this article. You can use the regular JavaScript array methods. You don't need any special methods or techniques to iterate over an array of objects. There are other statements like for and for…of in JavaScript that can do the same thing. It gives access to each object present inside an array. for each key from obj1, falling back to the value from obj2 ifĬonst result = uniqueKeys.The forEach() method can be used to loop through the array of objects in JavaScript. Reduce the unique keys into a new object containing the value

then spread the unique values into a new array.Ĭonst uniqueKeys = Convert the array of keys to a set to remove duplicate values, Spread the keys from both objects into an array.Ĭonst allKeys = We can also create generic functions for the reduce statements in examples 4 and 5:

If you want to ensure that only certain properties will be included in the result, Example 4 is a better choice, but Example 5 is useful when you only need to ensure that certain properties will never included. If you add a new property to the 'person' object it _will_ appear in the result unless you also add the property name to the disallowed properties. Const sum = numbers.reduce((next, number) => Įxample 5 reduces the keys from the 'person' object into a new object that only contains the properties whose keys are _not_ included in the 'disallowedProperties' array.