Trim last character from a string

Question

I have a string say

\"Hello! world!\" 

I want to do a trim or a remove to take out the ! off world but not off Hello.

Answer 1

If you want to remove the '!' character from a specific expression("world" in your case), then you can use this regular expression

string input = "Hello! world!";

string output = Regex.Replace(input, "(world)!", "$1", RegexOptions.Multiline | RegexOptions.Singleline);

// result: "Hello! world"

the $1 special character contains all the matching "world" expressions, and it is used to replace the original "world!" expression