cachebuster.cs

// Cachebuster for C#

private const string LinkTag = "<link href=\"{0}\" type=\"text/css\" rel=\"stylesheet\" />";
private const string JavascriptTag = "<script src=\"{0}\" type=\"text/javascript\"></script>";

private String MapAsset(String url)
{
  FileInfo file = new FileInfo(Server.MapPath("~" + url));
  String format = file.Extension == ".js" ? JavascriptTag : LinkTag;

  url = file.Exists ? String.Format("{0}?{1}", url, file.LastWriteTime.Ticks) : url;

  return String.Format(format, url);
}

//<link href="/path/to/your/stylesheet.css?lastwritetime" type="text/css" rel="stylesheet" />