Program.cs

public static void Main(string[] args)
{
    var sourceCode = @"class HelloKittyPrinter
                        {
                            public void Print()
                            {
                                System.Console.WriteLine(""Hello Hello Kitty!"");
                            }
                        }";
    var compiledAssembly = CompileSourceCodeDom(sourceCode);
    ExecuteFromAssembly(compiledAssembly);
}

private static Assembly CompileSourceCodeDom(string sourceCode)
{
    CodeDomProvider csharpCodeProvider = new CSharpCodeProvider();
    var cp = new CompilerParameters();
    cp.ReferencedAssemblies.Add("System.dll");
    cp.GenerateExecutable = false;
    CompilerResults cr = csharpCodeProvider.CompileAssemblyFromSource(cp, sourceCode);

    return cr.CompiledAssembly;
}