Regular expression to count number of commas in a string

Question

How can I build a regular expression that will match a string of any length containing any characters but which must contain 21 commas?

Answer 1

Exactly 21 commas:

^([^,]*,){21}[^,]$

At least 21 commas:

^([^,]?,){21}.*$

Answer 2

What language? There's probably a simpler method.

For example...

In CFML, you can just see if ListLen(MyString) is 22

In Java, you can compare MyString.split(',') to 22

etc...

Answer 3

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