Question

I have a text (string) that I want in all upper case, except the following:

1. Words starting with : (colon)
2. Words or strings surrounded by double quotation marks, “”
3. Words or strings surrounded by single quotation marks, ”

Everything else should be replaced with its upper case counterpart, and formatting (whitespaces, line breaks, etc.) should remain.

How would I go about doing this using Regex (C# style/syntax)?

Answer 1

I think you are looking for something like this:

text = Regex.Replace(text, @":\w+|""[^""]*""|'[^']*'|(.)",
                     match => match.Groups[1].Success ?
                              match.Groups[1].Value.ToUpper() : match.Value);

• :\w+ – match words with a colon.

• "[^"]*"|'[^']*' – match quoted text. For escaped quotes, you may use:

  "[^"\\]*(?:\\.[^"\\]*)*"|'[^'\\]*(?:\\.[^'\\]*)*'
  

• (.) – capture anything else (you can also try ([^"':]*|.), it might be faster).

Next, we use a callback for Regex.Replace to do two things:

• Determine if we need to keep the text as-is, or
• Return the upper-case version of the text.

Working example: http://ideone.com/ORFU8