[CommandMethod("GDBT")]
public Double GetDistanceBetweenTwoPoints()
{
Document acDoc = Application.DocumentManager.MdiActiveDocument;
PromptDoubleResult pDblRes;
pDblRes = acDoc.Editor.GetDistance ("\nPick two points: ");
string p =pDblRes.Value.ToString();
double pDBL = Math.Round(Double.Parse(p),1);
return pDBL;
}