Javascript RegEx Exactly one Digit Pattern

Question

str = "33d4m"; //d for days and h for hours and m for min
patt=/^[1-9]+d/i;
result=patt.test(str);
document.write("Returned value: " +  result);

I want result return true if and only if there is one digit before d, i.e;less than 10days remaining or a few hours remaining like i want return true also on

str = "23h5m"

if two digit before d then return false
if two digit before h then return true.
Where i am going wrong.

Robbie · Accepted Answer · 2012-04-21T04:02:39.003

4

You could try this:

patt=/^\d{1,2}h|^\dd/i

It means:

   Match 1 or 2 digits followed by the literal 'h' 
OR match a single digit followed by the literal 'd'

edited Apr 21 '12 at 04:02

answered Apr 21 '12 at 03:49

Robbie

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Thanks, Outstanding approach. – Wasim A. Apr 21 '12 at 03:52
@Wasim Thanks, i just re-edited it, i changed the `[1-9]` character sets to `\d` digits because otherwise `20h5M` wouldn't match. – Robbie Apr 21 '12 at 03:57
i do understand that, i understand regex but can't creat it due to lack of practice with regex. Thanks again – Wasim A. Apr 21 '12 at 04:01

Joseph · Answer 2 · 2012-04-21T03:38:54.100

1

i think something like this would work:

patt=/^[1-9][dh]/i

edited Apr 21 '12 at 03:38

answered Apr 21 '12 at 03:27

Joseph

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can you put some sample cases. how much is "a few hours?" – Joseph Apr 21 '12 at 03:43
hours obviously will not be greater than 23 – Wasim A. Apr 21 '12 at 03:46
patt=/^[1-9]d|h/i is working for me, but i think it should not work. Why its working. it should return false on str = "23h" but it true, WHY? – Wasim A. Apr 21 '12 at 03:47
str = "10d 10h 7m"; here what pattern should return false because days are greater than or equal to 10 – Wasim A. Apr 21 '12 at 03:50

score 1 · Answer 3 · answered Apr 21 '12 at 03:27

1

The plus means "at least one" - remove it. You may also want to use [0-9] for all digits, but that is just a guess.

patt=/^[1-9]d/i;

answered Apr 21 '12 at 03:27

Dennis

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correct, if str = "23h34M" then it should also return true. is that possible – Wasim A. Apr 21 '12 at 03:30
this comment makes no sense, there is no correlation between it return false for 33d4M but true for 23h34M. to have a regex work you need a pattern...what's the pattern? – Michael Frederick Apr 21 '12 at 03:36
pattern is [1-9]d or [1-9][1-9]h , basically d for days and h for hours. i need return true if days are less than 10 or few hours left – Wasim A. Apr 21 '12 at 03:38

Javascript RegEx Exactly one Digit Pattern

3 Answers3