How to convert a string of numbers to an array of numbers?

Question

I have below string -

var a = \"1,2,3,4\";

when I do -

var b = a.split(\',\');

I get b as

Answer 1

Since all the answers allow NaN to be included, I thought I'd add that if you want to quickly cast an array of mixed values to numbers you can do.

var a = "1,2,3,4,foo,bar";

var b = a.split(',');

var result = b.map(_=>_|0) // Floors the number (32-bit signed integer) so this wont work if you need all 64 bits.

// or b.map(_=>_||0) if you know your array is just numbers but may include NaN.