Treat Digit as Number

Question

Possible Duplicate:
How do I Convert a String into an Integer in JavaScript?

Given the following code:

var n = '1';
var x = n + 2;

x is set to "12".

Assuming I cannot change the value of n, what the most efficient way to have x set to 3?

Is it necessary to use parseInt() here? Or is there a way to have JavaScript automatically treat the digit as a number?

If you are using parseInt() dont forget the second parameter 10 like parseInt(n,10) — Saju, Jan 08 '13 at 20:32
The suggested duplicate is not an exact duplicate. As my question points out, I already know about `parseInt()`. My question is if there is a way to simply have JavaScript treat the digit to be a number in the way it treated a number as a digit in the code example in my question, without explicitly parsing the string. — Jonathan Wood, Jan 08 '13 at 20:43

score 4 · Accepted Answer · answered Jan 08 '13 at 20:32

4

parseInt(n,10) would work. You can also do n^0 as a shortcut. In fact, there are several such shortcuts available, but parseInt is "best" because it's more obvious to a human reader.

answered Jan 08 '13 at 20:32

Niet the Dark Absol

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I find unary plus quite readable – John Dvorak Jan 08 '13 at 20:34
Xor zero is nice as well, I admit – John Dvorak Jan 08 '13 at 20:35

score 4 · Answer 2 · answered Jan 08 '13 at 20:33

4

You can add + before n, this way it will parse it to a number.

var x = +n + 2;

answered Jan 08 '13 at 20:33

Ricardo Alvaro Lohmann

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Treat Digit as Number

2 Answers2