String with Comma separated numbers to array of integer in javascript

Question

I am converting String with Comma separated numbers to a array of integer like,

 var string = "1,2,3,4"; 
 var array = string.replace(/, +/g, ",").split(",").map(Number); 

it returns array = [1,2,3,4];

But when ,

 var string = ""; 
 var array = string.replace(/, +/g, ",").split(",").map(Number); 

it returns array = [0];

I was expecting it to return array = []; can someone say why this is happening.

Answer 1

I would recommend this:

var array;
if (string.length === 0) {
    array = new Array();
} else {
    array = string.replace(/, +/g, ",").split(",").map(Number);
}