Javascript regex splitting words in a comma separated string

I am trying to split a comma separated string using regex.

var a = 'hi,mr.007,bond,12:25PM'; //there are no white spaces between commas var b = /(\S+?),(?=\S|$)/g; b.exec(a); // does not catch the last item. 

Any suggestion to catch all the items.

3 Answers

Use a negated character class:

/([^,]+)/g 

will match groups of non-commas.

< a = 'hi,mr.007,bond,12:25PM' > "hi,mr.007,bond,12:25PM" < b=/([^,]+)/g > /([^,]+)/g < a.match(b) > ["hi", "mr.007", "bond", "12:25PM"] 

Why not just use .split?

>'hi,mr.007,bond,12:25PM'.split(',') ["hi", "mr.007", "bond", "12:25PM"] 

If you must use regex for some reason:

str.match(/(\S+?)(?:,|$)/g) ["hi,", "mr.007,", "bond,", "12:25PM"] 

(note the inclusion of commas).

If you are passing a CSV file, some of your values may have got double-quotes around them, so you may need something a little more complicated. For example:

Pattern splitCommas = java.util.regex.Pattern.compile("(?:^|,)((?:[^\",]|\"[^\"]*\")*)"); Matcher m = splitCommas.matcher("11,=\"12,345\",ABC,,JKL"); while (m.find()) { System.out.println( m.group(1)); } 

or in Groovy:

java.util.regex.Pattern.compile('(?:^|,)((?:[^",]|"[^"]*")*)') .matcher("11,=\"12,345\",ABC,,JKL") .iterator() .collect { it[1] } 

This code handles:

• blank lines (with no values or commas on them)
• empty columns, including the last column being empty
• handles values wrapped in double-quotes, including commas inside the double-quotes
• but does not handle two double-quotes used for escaping a double quote-itself

The pattern consists of:

• (?:^|,) matches the start of the line or a comma after the last column, but does not add that to the group

• ((?:[^",]|"[^"]*")*) matches the value of the column, and consists of:

  • a collecting group, which collects zero or more characters that are:

    • [^",] is a character that's not a comma or a quote
    • "[^"]*" is a double-quote followed by zero or more other characters ending in another double-quote

  • those are or-ed together, using a non-collecting group: (?:[^",]|"[^"]*")

  • use a * to repeat the above any number of times: (?:[^",]|"[^"]*")*
  • and into a collecting group to give the columns value: ((?:[^",]|"[^"]*")*)

Doing escaping of double quotes is left as an exercise to the reader