JavaScript React Basics Understanding State Bind Event Handlers to Components

What does Component instance mean?

When you create a class component that extends from React.Component, any custom methods you create are not bound to the component by default. You need to bind your custom methods, so that this refers to the component instance. In this video, we'll go over the ways to bind the this context in React.

3 Answers

joelearner
joelearner
38,663 Points

Hi Ula,

This sounds like OOP(object oriented programming). The teacher is saying that React.Component is a class. You have the ability in OOP to create your own definitions without impacting the original class, which is called creating an instance of the class.

Here, the teacher is saying that he will create a component variable based on the original class. Does this make sense?

Cheers!

i think React.Component is a function constructor

Ezra Siton
Ezra Siton
12,624 Points

React.Component is a "build-in" class (With methods, Properties). https://reactjs.org/docs/react-component.html

For example one "build-in" method of React.Component is render().

In our code, we extend (==> Create child of another class) from React.Component. Like this, we can use render() or constructor() without creating this methods inside our class + Add our own methods (Like "incramentsScore").

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes/extends

This is not so simple Concept (You should learn a little about OOP).

The most basic example: All birds class have a walk method (And properties like "name" of "weight").
Flying-birds extends "birds class" and add the "flying" method (Under `Flying-Birds" class you won't get an error if you run "walk" function =========> Same idea for the relationship between "Counter" class and "React.Component" class).