Check if an array is empty in React Native

Question

How can I check if an array is empty with a IF statment?

I have this array 'acessos' that's empty

... constructor(props){     super(props);     this.state = {       acessos:[]     };   } ... 

Then I'm trying to check if 'acessos' is empty and if it is I push some data in it. I've tried with null but with no results, so how can I check if is empty?

... if(this.state.acessos === null){       this.state.acessos.push({'uuid': beacons.uuid, 'date':date});       this.setState({acessos: this.state.acessos}); } else { ... 

Answer 1

I agree to Julien. Also you don't have to compare it to null. You can write it like

this.state.acessos && this.state.acessos.length > 0 

Answer 2

Just check if your array exists and has a length:

if (this.state.products && this.state.products.length) {      //your code here } 

No need to check this.state.products.length > 0.
0 is falsy anyway, a small performance improvement.