Regex replace only matched strings - C# -

i'm trying work out how use regex.replace method needs, need find particular word doesn't have "a-z" letters either side of , replace matches word.

in example below search "man" occurrences , replace "coach". use regex pattern "[^a-z](man)[^a-z]" capture want.

//string search "the man managed football team"  //after using regex.replace expect see "the coach managed football team"  //but "the coach coachaged football team" 

you need \b aka word boundary.

\b assert position @ word boundary (^\w|\w$|\w\w|\w\w) 

use \bman\b

see demo.

https://regex101.com/r/yg7zb9/31

your regex replace 5 characters always.\b 0 width assertion doesnt consume character.

string strregex = @"\bman\b"; regex myregex = new regex(strregex, regexoptions.multiline); string strtargetstring = @"the man managed football team"; string strreplace = @"coach";  return myregex.replace(strtargetstring, strreplace);