Google Search: find file extension with regex in c#

I have had a search to my page where I know the reader probably didn't find what they were looking for.

This post is to hopefully let that user find the information that they are looking for better.

The Search term was "find file extension with regex in c#".

A simple regex that could be used in C# to find file extensions is:


This will find an extension that is at the end of the string. To find an extension anywhere in a string you can use:


A regex to find a three letter extension at the end of a line:


To find a three letter extension anywhere in a string you can use:


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