Javascript like send callback function in C#

callback.cs

static void Main(string[] args)
{
    // sample Callback in C#
    string message = "Done!";
    startRunner(finished, message);
}
static public void finished(string message)
{
    Console.Write(message);                        
}
static public void startRunner(Action<string> callback, string message)
{
    // do something
    Console.Write("Running");
    callback(message);
}