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JavaScript React Basics (2018) Understanding State Create a Stateful Component

Why is an object property initialized with = ?

I know the objects have key:value or methods, or array but I do not understand in the video when Guil created state like

state = {


what do we call that sort? I heard key: value, arrays, booleans but is it object assigned to a property? If so why we use equal?

1 Answer

Michael Hulet
Michael Hulet
47,911 Points

state is a property on the Counter class. Properties are just like normal variables, but they're values contained by an object. Take this code for example:

const a = 1; // a is now 1

const obj = {}; // obj is a new object
obj.a = 2; // obj.a is 2

const otherObj = {};
otherObj.a = 3; //otherObj.a is 3

console.log(a); // Logs 1
console.log(obj.a); // Logs 2
console.log(otherObj.a); // Logs 3

Notice how in all those cases, the = operator was used to assign the value to each property, just like it was the normal constant at the top. In the video, state is a property on this (and this equal to the new Counter object). When each new Counter is created, it will be given a property called state, which will be equal to another new object, which itself will have a property called score, which will start as 0