NetSwitch.cs

using System;
using System.Text;

class Evil
{
    string changeCase(string caseType, params string[] words)
    {
        // Sanitize the input
        caseType = caseType.Trim().ToLower();

        // Accumulate result in StringBuilder
        var result = new StringBuilder();

        // We currently support lower and camel case
        if (caseType == "lower")
        {
            // Every word is converted to lower
            // And concatenated
            foreach (var word in words)
            {
                result.Append(
                    word
                        .Trim()
                        .ToLower());
            }
        }
        else if (caseType == "camel")
        {
            // First word is lower
            result.Append(
                words[0]
                    .Trim()
                    .ToLower()
            );

            // Subsequent words are Proper case
            for (var offset = 1;
                 offset < words.Length;
                 offset++)
            {
                // First letter is uppercase
                result.Append(
                    words[offset]
                        .Substring(0, 1)
                        .ToUpper());

                // Rest of the letters are lowercase
                result.Append(
                    words[offset].
                        Substring(1).
                        ToLower());
            }
        }
        return result.ToString();
    }
    
    static void Main(string[] args)
    {
        Evil obj = new Evil();
        Console.WriteLine(obj.changeCase("camel", "Two", "Words"));
    }
}