gistfile1.txt

public static class StringExtensions {

  /// <summary>
  /// Null safe value of .Trim(). If the value is null, returns an empty string.
  /// </summary>
  public static string TrimNullSafe(this string value) {
	  return (value != null)
		? value.Trim()
		: String.Empty;
	}
}

var upcCode = UPCCode.Text.TrimNullSafe();

if (!String.IsNullOrEmpty(upcCode)) {
  // update db
}