What is the most efficient way to detect if a string contains a number of consecutive duplicate characters in C#?

Question

For example, a user entered \"I love this post!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!\"

the consecutive duplicate exclamation mark \"!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!\" should b

Answer 1

Here's and example of a function that searches for a sequence of consecutive chars of a specified length and also ignores white space characters:

    public static bool HasConsecutiveChars(string source, int sequenceLength)
    {
        if (string.IsNullOrEmpty(source))
            return false;
        if (source.Length == 1) 
            return false;

        int charCount = 1;
        for (int i = 0; i < source.Length - 1; i++)
        {
            char c = source[i];
            if (Char.IsWhiteSpace(c))
                continue;
            if (c == source[i+1])
            {
                charCount++;
                if (charCount >= sequenceLength)
                    return true;
            }
            else
                charCount = 1;
        }

        return false;
    }

Edit fixed range bug :/