Question

I have a sentence that may have “not, or” inside.

Currently, I’m trying to test and remove these words, however, I couldn’t figure out how to write a correct regex test pattern, can someone help please?

I tried with

string test= ""; 
string str=" some words here ";

if (str.ToLower().Contains(" not ")) {
    test = str.ToLower().Replace(" not ", " "); 
} else if (str.ToLower().Contains(" or ")) { 
    test = str.ToLower().Replace(" or ", " ");
} 

Answer 1

I think you mean to replace “not” and “or”

string resultString = null;
try {
    resultString = Regex.Replace(subjectString, "(?:not|or)", "", RegexOptions.Singleline | RegexOptions.IgnoreCase);
} catch (ArgumentException ex) {
    // Syntax error in the regular expression
}