How to Find and Replace Object in an Array JavaScript?

Are you wondering how we find and replace object in an array in JavaScript? Well, read on to learn new insights.

In this article, we’ll show you several methods of how to replace object in an Array.

Are you ready to discover the secrets to finding and replacing objects in an array using JavaScript?

Let’s get started exploring several methods, including the powerful map() and splice() methods, to update your arrays with ease.

How to replace an object in an array in JavaScript?

You can replace an object in an array by first locating the object you want to replace and then updating it with the new object.

Let’s break down the process step by step:

1. Locate the Object

To replace an object, you need to find its index in the array.

You can use methods like indexOf() or a loop to search for the object based on specific criteria.

2. Create a New Object

Once you have identified the object to replace, create a new object with the desired changes or values.

3. Replace the Object

Finally, replace the old object in the array with the newly created one. You can use the array index to accomplish this.

What are the different methods to replace an object in an array in JavaScript

There are several methods that we can able to use to replace an object in an array using JavaScript. Here are some methods:

Method 1: Use the map() method

The map() method in JavaScript is a powerful tool for replacing objects in an array while preserving the original array.

It creates a new array with the modified objects based on a provided callback function.

Here’s an example:

const sampleArray = [
  { id: 1, name: 'Andrea' },
  { id: 2, name: 'Bea' },
  { id: 3, name: 'Criza' },
];

const updatedArray = sampleArray.map(obj => { ✅
  if (obj.id === 1) {
    return { ...obj, name: 'Itsourcecode' };
  }
  return obj;
});

console.log(updatedArray);

In our given example, we use the map method to create a new array with the results of calling a provided function on every element in the calling array.

In this case, the function checks if the id property of the current object is equal to 1.

If it is, the function returns a new object with the same properties as the current object, but with the name property updated to ‘Itsourcecode.’

If the id property is not equal to 1, the function returns the current object unchanged.

Output:

[
  { id: 1, name: 'Itsourcecode' },
  { id: 2, name: 'Bea' },
  { id: 3, name: 'Criza' }
]

Method 2: Use the splice() method

The splice() method allows you to modify an array by removing, adding, or replacing elements.

To replace an object, specify the index and the number of elements to remove, and then add the new object.

Here’s an example:

const employee = [
  { name: 'Andrea', age: 18 },
  { name: 'Bea', age: 19 },
  { name: 'Criza', age: 20 }
];

const index = employee.findIndex(employee => employee.name === 'Andrea');
if (index !== -1) {
  employee.splice(index, 1, { name: 'Itsourcecode', age: 21 });✅
}

console.log(employee);

As you can see in our given example: we use the findIndex method to find the index of the object with the name property equal to ‘Andrea.’

If the object is found (i.e., index is not -1), the splice method is used to remove one element at the specified index and replace it with a new object { name: ‘Itsourcecode’, age: 21 }.

Output:

[
  { name: 'Itsourcecode', age: 21 },
  { name: 'Bea', age: 19 },
  { name: 'Criza', age: 20 }
]

Use a for loop with the splice method

This method allows you to iterate over each element in the array and check if it satisfies a certain condition.

If it does, you can use the splice method to remove or replace existing elements in an array at the desired index.

Here’s an example:

const employee = [
  { name: 'Andrea', age: 18 },
  { name: 'Bea', age: 19 },
  { name: 'Criza', age: 20 }
];

for (let i = 0; i < employee.length; i++) { ✅
  if (employee[i].name === 'Andrea') {
    employee.splice(i, 1, { name: 'Itsourcecode', age: 18 });
    break;
  }
}

console.log(employee);

It uses a for loop to iterate over each element in the employee array.

If the name property of the current element is equal to ‘Andrea’, the splice method is used to remove one element at the current index (i) and replace it with a new object { name: ‘Itsourcecode’, age: 18 }.

The break statement is used to exit the loop once the replacement has been made.

Output:

[
  { name: 'Itsourcecode', age: 18 },
  { name: 'Bea', age: 19 },
  { name: 'Criza', age: 20 }
]

Conclusion

Replacing an object in an array in JavaScript can be achieved through various methods, such as using the map() method, the splice() method, or a for loop with the splice method.

These methods allow you to locate the object you want to replace, create a new object with the desired changes or values, and finally replace the old object in the array with the newly created one.

We hope this article has provided you with enough information to help you understand the replace object in array JavaScript.

If you want to dive into more JavaScript topics, check out the following articles:

• regex special characters JavaScript
• Remove duplicates from array JavaScript
• Void functions in JavaScript

Thank you for reading Itsourcecoders 😊.

Caren Bautista

Technical Writer at PIES IT Solution

Responsible for crafting clear, well-structured, and beginner-friendly content across the platform. Handles the writing, proofreading, and editorial review of tutorials, guides, and documentation to ensure every article is accurate, readable, and easy to follow.

Expertise: Technical Writing · Content Creation · Documentation · Editorial Writing · JavaScript · TypeScript · Python · Python Errors · HTTP Errors · MS Excel  · View all posts by Caren Bautista →