Can we use regex in robots.txt file to block URLs?
Regular Expressions are not valid in robots.txt, but Google, Bing and some other bots do recognise some pattern matching.
Say if you wanted to block all URLs that have a
example any where in the URL, you can use a wild card entry *
User-agent: * Disallow: /*example
You can also use the dollar sign $ to specify that the URLs must end that way. So if you wanted to block all URLs that end with
example, but not URLs that had a
example elsewhere in the URL you could use:
User-agent: * Disallow: /*example$
More in-depth info for Google can be found here: Robots.txt Specifications, Bing here: How to Create a Robots.txt file and there is a an interactive guide on Moz here