How To Split And Modify A String In Nodejs?

I have a string : var str = '123, 124, 234,252'; I want to parse each item after split and increment 1. So I will have: var arr = [124, 125, 235, 253 ]; How can I do that in Node

Solution 1:

Use split and map function:

var str = "123, 124, 234,252";
var arr = str.split(",");
arr = arr.map(function (val) { return +val + 1; });

Notice +val - string is casted to a number.

Or shorter:

var str = "123, 124, 234,252";
var arr = str.split(",").map(function (val) { return +val + 1; });

edit 2015.07.29

Today I'd advise against using + operator to cast variable to a number. Instead I'd go with a more explicit but also more readable Number call:

var str = "123, 124, 234,252";
var arr = str.split(",").map(function (val) {
  returnNumber(val) + 1;
});
console.log(arr);

edit 2017.03.09

ECMAScript 2015 introduced arrow function so it could be used instead to make the code more concise:

var str = "123, 124, 234,252";
var arr = str.split(",").map(val =>Number(val) + 1);
console.log(arr);

Solution 2:

var str = "123, 124, 234,252";
var arr = str.split(",");
for(var i=0;i<arr.length;i++) {
    arr[i] = ++arr[i];
}

Solution 3:

If you're using lodash and in the mood for a too-cute-for-its-own-good one-liner:

_.map(_.words('123, 124, 234,252'), _.add.bind(1, 1));

It's surprisingly robust thanks to lodash's powerful parsing capabilities.

If you want one that will also clean non-digit characters out of the string (and is easier to follow...and not quite so cutesy):

_.chain('123, 124, 234,252, n301')
   .replace(/[^\d,]/g, '')
   .words()
   .map(_.partial(_.add, 1))
   .value();

2017 edit:

I no longer recommend my previous solution. Besides being overkill and already easy to do without a third-party library, it makes use of _.chain, which has a variety of issues. Here's the solution I would now recommend:

const str = '123, 124, 234,252';
const arr = str.split(',').map(n =>parseInt(n, 10) + 1);

My old answer is still correct, so I'll leave it for the record, but there's no need to use it nowadays.