Showing left side zeros formating strings - Objective-C

Question

I am trying to implement a chronometer on my app, but the left side zeros won't show up. Do you know any way to make them default?

Here's what I am trying:

self.text.string = [NSString stringWithFormat:@"%2.0d:%2.0d:%1.0d", minute, second, decimals];

Here's what I really see:

2014-01-04 15:55:06.462 appchrono[17556:70b]   :3:2
2014-01-04 15:55:06.562 appchrono[17556:70b]   :3:3

Here's what I want it to be:

2014-01-04 15:55:06.462 appchrono[17556:70b]   00:03:2
2014-01-04 15:55:06.562 appchrono[17556:70b]   00:03:3

Any help? Thank you!

Stackoverflow search didn't return this topic to me at that time.. :( — RickON, Jan 04 '14 at 18:29

score 1 · Accepted Answer · answered Jan 04 '14 at 18:00

1

You're close:

 self.text.string = [NSString stringWithFormat:@"%02d:%02d:%02d", minute, second, decimals];

answered Jan 04 '14 at 18:00

godel9

score 0 · Answer 2 · edited Jan 04 '14 at 18:59

0

Try %-2.2d. This tells the formatter to prefix zeroes.

edited Jan 04 '14 at 18:59

rmaddy

answered Jan 04 '14 at 18:04

uulhaa

May not make sense, but it works. – uulhaa Jan 04 '14 at 18:12
I just tried this and to my surprise this does actually give the right result. However, the more correct format would be `%02d`. The fact that `%-2.2d` actually works is pretty strange on very non-obvious. – rmaddy Jan 04 '14 at 18:27
You are very right. But I just remembered this from my printf days (1985...). In those day %02 usually did not work (depending on the actual OS being used), so we used the other. – uulhaa Jan 04 '14 at 18:33

2 Answers2