Regex to remove single-line SQL comments (--)

Question

Question:

Can anybody give me a working regex expression (C#/VB.NET) that can remove single line comments from a SQL statement ?

I mean these comments:

Answer 1

This seems to work well for me so far; it even ignores comments within strings, such as SELECT '--not a comment--' FROM ATable

    private static string removeComments(string sql)
    {
        string pattern = @"(?<=^ ([^'""] |['][^']*['] |[""][^""]*[""])*) (--.*$|/\*(.|\n)*?\*/)";
        return Regex.Replace(sql, pattern, "", RegexOptions.IgnorePatternWhitespace | RegexOptions.Multiline);
    }

Note: it is designed to eliminate both /**/-style comments as well as -- style. Remove |/\*(.|\n)*?\*/ to get rid of the /**/ checking. Also be sure you are using the RegexOptions.IgnorePatternWhitespace Regex option!!

I wanted to be able to handle double-quotes too, but since T-SQL doesn't support them, you could get rid of |[""][^""]*[""] too.

Adapted from here.

Note (Mar 2015): In the end, I wound up using Antlr, a parser generator, for this project. There may have been some edge cases where the regex didn't work. In the end I was much more confident with the results having used Antlr, and it's worked well.