c# - how to replace richtextbox.rtf if and only if the whole word match? -

c# - how to replace richtextbox.rtf if and only if the whole word match? -

my original replace code is.

rttextarea.rtf = rttextarea.rtf.replace(oldtext, newtext);

but problem replaces occurence of words instead of required word e.g origianl word :- hello name serak , in state of israel replace() -- whole word chages "are serak , in arereal"

is there anyway can include status or match whole word? working environment c#.

use regular expressions. in illustration \b represents word boundary.

var regexp = new system.text.regularexpressions.regex(@"\bis\b"); rttextarea.rtf = regexp.replace(rttextarea.rtf, "are");

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