2f34435-something.jpg
4t44234-something.jpg
5465g67-something.jpg
says I have 3 string above, without using split, how can I do regex to get the value before dash? the length of strings is not consistent though..
4 Answers
One option would be to match one or more non-dash characters at the beginning of the string:
^[^-]+
^- Anchor that denotes the beginning of the string[^-]- Character set to match all characters that are not dashes.+- One or more occurrences of non-dash characters.
For instance:
'2f34435-something.jpg'.match(/^[^-]+/);
// ["2f34435"]
With the .split() method, you would just need to retrieve the first match:
'2f34435-something.jpg'.split('-')[0];
// "2f34435"
Comments
you can use...
/^(.+?)-/gm
which will capture all 3 ( or as many as you have )
You can see it in action here https://regex101.com/r/gD5sU2/2
This will also handle if you get - in the rest of the filename...
such as :-
2f34435-something-else.jpg
4t44234-something.jpg
5465g67-something.jpg
5 Comments
Jennifer
what does the plus sign do here? and do we need bracket?
Keith Nicholas
. is any character and + is 1 or more
Keith Nicholas
the brackets indicate the part you want to capture
Jennifer
I found the
^ is not required.Keith Nicholas
oh, it isn't in the examples, it was supposed to handle if there was another - in the filename, but that doesn't quite work.... I'll update my answer
([a-z0-9]+)-[a-z0-9]+.jpg matches each of those strings and the string returned from the first group will match the text before the dash.
str.substring(0, str.indexOf('-'));