Generate hash of a text

public static string TextToHash(string text)
  {
      var sh = SHA1.Create();
      var hash = new StringBuilder();
      byte[] bytes = Encoding.UTF8.GetBytes(text);
      byte[] b = sh.ComputeHash(bytes);
      foreach (byte a in b)
      {
          var h = a.ToString("x2");
          hash.Append(h);
      }
      return hash.ToString();
  }