Regex for comma separated text

Question

I create a text field for adding tags separated by commas. (e.g. php, jquery, js, ruby on rails) The field is like the one on stakoverflow where you add tags for posts.

Answer 1

Why not use the str_getcsv function, It will parse the CSV string into an array and then you can validate each tag individually using the ctype_alnum function and discard the malformed ones ;)

Here is the correct regex pattern if you really need it:-

'/^[a-z0-9]+(, [a-z0-9]+)*$/i'

Answer 2

OK, there are a few problems here:

1. There is no php function called "regex_match"
2. a function uses (), not []
3. variables start with $. The inside of [] is an index.

The line you posted will result in a syntax error in PHP. Since you "tested it", it means this is not really the code you used. Please post the actual code.

About the regex, it's a good first try, but you forgot the numbers:

/^[a-z,0-9 ]+$/i