Regex.Replace() for replacing the whole occurrence

Question

Hi,

Am using regex.Replace() to replace the whole occurrence of a string.. so I gave like Regex.Replace(str,@stringToReplace,"**"); where stringToReplace = @"session" + "\b";

if i give like that its not replacing.. but if i give like Regex.Replace(str,@"session\b","**"); then its working.. how to avoid this.. i want to pass value which will be set dynamically..

Thanks nimmi

Answer 1

try

stringToReplace = @"session" + @"\b";

Answer 2

@"session" + "\b" and @"session\b"

are not the same string. In the first case "\b" you don't treat the slash as a slash but as an escape parameter. In the second case you do.

So @"session" + @"\b" should bring the same result

Answer 3

The @ here means a verbatim string literal.

When you write "\b" without the @ it means the backspace character, i.e. the character with ASCII code 8. You want the string consisting of a backslash followed by a b, which means a word boundary when in a regular expression.

To get this you need to either escape the backslash to make it a literal backslash: "\\b" or make the second string also into a verbatim string literal: @"\b". Note also that the @ in @"session" (without the \b) doesn't actually have an effect, although there is no harm in leaving it there.

stringToReplace = "session" + @"\b";