score:0
the concept of object destructuring is an es6 feature which enables the user to use the properties of an object.in this case you are using the state object for destructring.
example without destructuring:
state={cat:'meaow',dog:'bark'}
render(){
return(
<div>
<h2>{this.state.cat}</h2>
<h2>{this.state.dog}</h2>
</div>)
}
example with destructuring:
state={cat:'meaow',dog:'bark'}
render(){
const {cat,dog}=this.state
return(
<div>
<h2>{cat}</h2>
<h2>{dog}</h2>
</div>)
}
score:1
this line of code
const {cat} = this.state
is destructor syntax. it's simply take the cat
state from this.state
. so you dont have to write this.state.cat
every time inside render function but just simply use cat
score:1
const {cat} = this.state
it's called object destructuring assignment.
it's way flexible if you have many fields in your state
or props
object.
something like:
const { cat, dog, ...otheranimals } = this.state;
Source: stackoverflow.com
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