How to remove prototype in javascript

JavaScript is an object-oriented programming language, in which objects have prototype properties, namely prototype. The prototype of an object stores the prototype chain information of the object, which is a very useful feature in JavaScript. But sometimes, we need to use JavaScript to remove the prototype, this function is also very important.

1. What is a prototype?

Before introducing how to remove prototypes, we need to first understand the concept of prototypes. In JavaScript, the prototype of an object points to another object, and the pointed object also has its own prototype, until the prototype of an object is null.

In the above prototype chain, if an object does not find the required properties or methods in its own properties, it will look for it in its prototype chain. This is how the prototype chain works.

2. When you need to remove the prototype

In most cases, we do not need to remove the prototype of the object, but in some cases, it is necessary to remove the prototype . For example:

2.1 Need to convert an object into a simple object

If an object has a prototype, then it is not a simple object (plain object) because it inherits all the objects in its prototype chain Object properties and methods. If you need to convert this object to a simple object, you need to remove the prototype first.

2.2 Avoid prototype chain pollution

Some JavaScript frameworks define some properties and methods on global objects, which may cause serious naming conflicts. In order to avoid pollution of the prototype chain, we need to remove the prototype of an object.

2.3 Need to shape objects into other types

In order to implement certain algorithms or functions, sometimes we need to convert an object into an instance of other types. For example, we need to convert an ordinary JavaScript object into an instance of the Date type. We can first remove the prototype of this object and then reset its prototype to Date.prototype.

3. How to remove the prototype

In JavaScript, we can use the Object.setPrototypeOf method to set the prototype of an object to null to remove the prototype of this object. . This method requires two parameters: a target object and a prototype object. In scenarios where we need to remove the prototype, the prototype object parameter should be set to null.

The following is a sample code:

const myObj = {
  prop1: 'value1',
  prop2: 'value2'
};

console.log(myObj.__proto__); // 输出: {}

Object.setPrototypeOf(myObj, null);

console.log(myObj.__proto__); // 输出: undefined

In this sample code, we first define an object containing two properties. Then we set the prototype of this object to null through the Object.setPrototypeOf method. Finally, we print the prototype of this object and find that the prototype has been successfully removed.

In addition to using the Object.setPrototypeOf method, we can also use the Object.create method to create an object without a prototype. When creating a new object, you can set the prototype parameters to null and then add any properties and methods you need.

The following is a sample code:

const myObj = Object.create(null);
myObj.prop1 = 'value1';
myObj.prop2 = 'value2';

console.log(myObj.__proto__); // 输出: undefined

In this sample code, we use the Object.create method to create an object without a prototype, and then add two properties. Finally we print the prototype of this object and find that it is undefined.

4. Summary

In JavaScript, the prototype chain is one of the very important concepts, but sometimes we need to remove the prototype of the object in order to achieve certain function or algorithm. The prototype of an object can be removed using the Object.setPrototypeOf method or the Object.create method. When a prototype is removed, the object will no longer inherit any properties or methods from the prototype chain.

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