Regular Expressions - Strong Password Validation

string r =
        @"(?x)" +                           // Ignore spaces within regex expression, for readability
        @"^"    +                           // Anchor at start of string
        @"(?=.* ( \d | \p{P} | \p{S} ))" +  // String must contain a digit or punctuation char or symbol
        @".{6,}";                           // String must be at least 6 characters in length

Console.WriteLine (Regex.IsMatch ("abc12", r));
Console.WriteLine (Regex.IsMatch ("abcdef", r));
Console.WriteLine (Regex.IsMatch ("ab88yz", r));

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