Question

How to check if array contains empty elements in Node.js

Answer 1

const arr = ['c', 'node.js', , , null, '', 'c++', false];
 
if (arr.indexOf(undefined) === -1 && arr.includes(undefined)) {
    console.log('yes');
} else {
    console.log("no");
}
 
 
   
   
   
/*
run:
   
yes
   
*/

 

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Answer 2

const arr = ['c', 'node.js', , , '', 'c++', undefined];

if (arr.indexOf(undefined) === -1 && arr.includes(undefined)) {
  	console.log('yes');
} else {
  	console.log("no");
}

console.log(arr.includes(undefined));
  
  
  
  
/*
run:
  
no
true
  
*/

 

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