advanced code snippet search

Posted By

darkphotn on 01/13/08


Tagged


Versions (?)

Who likes this?

1 person have marked this snippet as a favorite

luman


Convert String to Number in Javascript

 / Published in: JavaScript
 

Javascript sometimes confuses strings and numbers. When this happens, you get bizarre outcomes such as "2 + 2 = 22". The following code FORCES a conversion to a number.

Expand | Embed | Plain Text 
  1. var myval = Number(document.myform.mytext.value);
  2.  
  3. //var myval = document.myform.myval.value; myval++; myval--;

Report this snippet  

Comments

RSS Icon Subscribe to comments
Posted By: tpsreport on January 13, 2008

Do not use this code! This is amateur-level fail. Javascript has plenty of type-casting functions available that do this properly.

Given an input value of x, you can do the following:

parseInt(x, 10) // returns x as an integer in base 10 parseInt(x, 16) // returns x as an integer in hex parseFloat(x) // returns x as a float

See the Mozilla reference docs here: http://developer.mozilla.org/en/docs/CoreJavaScript1.5Guide:PredefinedFunctions:parseIntandparseFloat_Functions

Posted By: darkphotn on January 13, 2008

This is a quick and dirty one-line hack that works.

A more professional method would be:

function $n (n) { return (typeof(n) == 'number') ? new Number(n) : NaN; } // originally posted by inamorix

Posted By: darkphotn on January 13, 2008

Original code modified -- the new method is based on inamorix's, and is better than the original (and also better than tps's).

tpsreport, that link is dead. Check the page.

You need to login to post a comment.