Converting strings to PascalCase

I have a method which I use on occasion to convert strings (like enum and property names) to PascalCase for display.

It's fairly simple, so there's probably not much to comment on, but as usual I appreciate any advice on improving it.

/// 
/// Converts a string of dash-separated, or underscore-separated words to a PascalCase string.
/// 
/// The string to convert.
/// The resulting PascalCase string.
public static string ToPascalCase(this string s)
{
    string[] words = s.Split(new char[2] { '-', '_' }, StringSplitOptions.RemoveEmptyEntries);

    StringBuilder sb = new StringBuilder(words.Sum(x => x.Length));

    foreach (string word in words)
    {
        sb.Append(word[0].ToString().ToUpper() + word.Substring(1));
    }

    return sb.ToString();
}

Feel free to use it if you like, as per my usual regards.

I think you should use Concat instead of StringBuilder:

public static string ToPascalCase(this string s)
{
    var words = s.Split(new[] { '-', '_' }, StringSplitOptions.RemoveEmptyEntries)
                 .Select(word => word.Substring(0, 1).ToUpper() + 
                                 word.Substring(1).ToLower());

    var result = String.Concat(words);
    return result;
}

This solution should not be as fast as manually looping through the original string, but I think it is much easier to read and follow. Unless you do those convertions like 1000000 times per second, you should not complicate things.

StackExchange Code Review Q#112769, answer score: 13