When working with JavaScript objects, you may come across a situation where you need to update only the parent object without modifying its children. This can be achieved using various methods to manipulate objects in JavaScript. Here are some techniques to change only the parent object:
1. Object.assign():
You can use the Object.assign() method to copy the properties from one or more source objects to a target object. This method does not modify the source objects and only changes the target object. Here's an example:
```javascript
let parentObj = { name: 'John', age: 30 };
let childObj = { hobbies: ['reading', 'hiking'] };
let updatedParentObj = Object.assign({}, parentObj, { age: 35 });
console.log(updatedParentObj); // Output: { name: 'John', age: 35 }
```
2. Spread Operator (…):
The spread operator (...) can also be used to create a new object with the properties of the parent object and then make modifications to it without affecting the original object. Here's an example:
```javascript
let parentObj = { name: 'John', age: 30 };
let updatedParentObj = { ...parentObj, age: 35 };
console.log(updatedParentObj); // Output: { name: 'John', age: 35 }
```
3. Object.create():
The Object.create() method can be used to create a new object with the specified prototype object and properties. This method does not modify the original parent object and only changes the newly created object. Here's an example:
```javascript
let parentObj = { name: 'John', age: 30 };
let updatedParentObj = Object.create(parentObj);
updatedParentObj.age = 35;
console.log(updatedParentObj); // Output: { age: 35 }
```
4. JSON.parse() and JSON.stringify():
You can also use the JSON.parse() and JSON.stringify() methods to create a deep copy of the parent object and then make changes to the copy without affecting the original object. Here's an example:
```javascript
let parentObj = { name: 'John', age: 30 };
let parentObjCopy = JSON.parse(JSON.stringify(parentObj));
parentObjCopy.age = 35;
console.log(parentObjCopy); // Output: { name: 'John', age: 35 }
```
By using these techniques, you can change only the parent object in JavaScript without altering its children. This can be useful when you need to update the parent object while preserving the integrity of its nested objects and arrays.
