private static string GetExtension(GuidanceExtensionEnum extension)
{
switch (extension)
{
case GuidanceExtensionEnum.FromA:
return "2";
case GuidanceExtensionEnum.FromB:
return "3";
case GuidanceExtensionEnum.FromBothPoints:
return "1";
case GuidanceExtensionEnum.None:
return "4";
}
return null;
}