Regular Expresion

[ONeil Tomlinson]

Hi I want to write a regular expression that will match when there is no "XXSP" at the begining of the string eg "XXSPPaabbcc1234" = No Match eg "XaXSPPaabbcc1234" = Match Thanks

[OriginalGriff]

Why use a regular expression?

if ((s.Length >= 5) && (!s.StartsWith("XXSP")
{
//Match
}

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[ONeil Tomlinson]

I need to use a Regular expression (im passing it to a Business rule engine)

[OriginalGriff]

Isn't it just "^XXSP" as in:

        string s1 = "XXSPHello";
        string s2 = "XaSPGoodbye";
        Regex r = new Regex(@"^XXSP");
        if (r.Match(s1).Success)
            {
            MessageBox.Show(s1);
            }
        if (r.Match(s2).Success)
            {
            MessageBox.Show(s2);
            }

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[MidwestLimey]

That will match any string starting with XXSP.

10110011001111101010101000001000001101001010001010100000100000101000001000111100010110001011001011

[MidwestLimey]

You can't use a Regex to not find a pattern, per se, as there are too many ways to not match. Instead you want to match and exclude anything that begins with XXSP. This should do the trick:

^((X[^X])|(XX[^S])|(XXS[^P])).*$

10110011001111101010101000001000001101001010001010100000100000101000001000111100010110001011001011

[ONeil Tomlinson]

Thanks dude that worked ;)