Question

This should turn out to be a fairly simple Regex, but I’m no expert in it. I am trying to match a sequence of specific letters, but I do not want them to match if its part of a whole word. I need to only capture the STA letters. Here’s an example:

My Regex: [Ss][Tt][Aa]

STA         -- Should Match
sta         -- Should Match
Start       -- Should NOT match
sta rt      -- Should Match
rt sta      -- Should Match
rtsta       -- Should NOT Match

Can someone help me out here please? This is C# .NET Regex, if it matters.

Answer 1

Use word boundary \b markers to match only whole words:

\b[Ss][Tt][Aa]\b