Question

Possible Duplicate:
Workarounds for JavaScript parseInt octal bug

I’m parsing a string to check if it’s a date, and by chance we now discovered that my method doesn’t work for dates in august or september. This is what I do (the input isn’t really hard-coded, obviously, but for brevity…):

var str = '2010-08-26 14:53';
var data = str.split(' ');  // ['2010-08-26', '14:53']
var date = data[0].split('-'); // ['2010', '08', '26]
var time = data[1].split(':'); // ['14', '53']

var yyyy = parseInt(date[0]); // 2010

// THIS IS WHERE STRANGE THINGS HAPPEN:
var MM = parseInt(date[1]); // 0 - not 08 or 8, as expected!
console.log(date[1]); // prints "08" (with quotes)
console.log(date[1].toString()); // prints 08 (no quotes)
console.log(parseInt(date[1].toString())); // prints 0 (!)

This problem arises for august and september, and for the 8th and 9th every month – that is, when either "08" or "09" is being parsed to integer, 0 is returned instead of 8 or 9. The code works for both lower (e.g. "07") and higher (e.g. "10") integers (at least within expected date ranges…)

What am I doing wrong?

Answer 1

Use

parseInt(date[1], 10)

to make sure the string is interpreted as base 10 (decimal).

Otherwise, it is interpreted as base 8 (octal) if it starts with "0", or as base 16 (hexadecimal) if it starts with "0x".

In fact, you should always include the base argument to avoid these kinds of bugs.