How to Modify an Array of Objects in React Using Values from Another Array

Learn how to update an array of objects in React by modifying it based on values from another array, complete with examples and code snippets.
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How to Modify an Array of Objects in React Using Values from Another Array

When working with React, you may come across situations where you have multiple arrays and need to modify one based on the values of another. This task can be quite common, especially when dealing with data fetched from APIs. In this post, we'll explore how to effectively update an array of objects based on another array using JavaScript in React.

The Problem

Suppose you have two arrays defined as follows:

[[See Video to Reveal this Text or Code Snippet]]

Objective

You want to update array1 so that each object reflects the name and age from array2. For instance:

The first object in array1 should have its name changed to "aman" and age to 26.

The second object in array1 should become { name: "rohan", age: "46" }.

The updated array1 should look like this:

[[See Video to Reveal this Text or Code Snippet]]

The Solution

To achieve this transformation, we can utilize the forEach method in JavaScript. This method allows us to iterate over one array and modify the corresponding elements of another array.

Step-by-Step Guide

1. Using forEach

[[See Video to Reveal this Text or Code Snippet]]

Explanation:

We loop through array1 using forEach, referencing each person object and its index.

Inside the loop, we set the name and age of person to the corresponding values from array2 based on the same index.

2. Handling Different Objects (Optional Update)

If your arrays do not line up perfectly (i.e., they might not have the same length or identical indices), you can use a more dynamic approach. For instance, if array1 objects have an id property to match:

[[See Video to Reveal this Text or Code Snippet]]

Alternative Explanation:

Here, instead of using the index, we use find to search for a corresponding object in array2 based on a condition. Make sure to adapt the property you’re matching on (uName, id, etc.) depending on your precise use case.

Result

After applying the above code snippets, you will obtain the following:

[[See Video to Reveal this Text or Code Snippet]]

Conclusion

In this post, we learned how to efficiently modify an array of objects in React using values from another array. By utilizing the forEach method, you can easily update the properties of your objects, whether they match in structure or not.

This technique is especially useful when dealing with data from APIs, ensuring your UI reflects the most accurate and up-to-date information. Happy coding!