Checking something isEmpty in Javascript?

Question

How can I check if a variable is empty in Javascript? Sorry for the stupid question, but I\'m a newbie in Javascript!

if(response.photo) is empty {
    do so         


        

Answer 1

Here my simplest solution.

Inspired by PHP empty function

function empty(n){
	return !(!!n ? typeof n === 'object' ? Array.isArray(n) ? !!n.length : !!Object.keys(n).length : true : false);
}

//with number
console.log(empty(0));        //true
console.log(empty(10));       //false

//with object
console.log(empty({}));       //true
console.log(empty({a:'a'}));  //false

//with array
console.log(empty([]));       //true
console.log(empty([1,2]));    //false

//with string
console.log(empty(''));       //true
console.log(empty('a'));      //false