Re: Units system in document

As indicated you need to convert the coordinates from millimeters to feet first in order to get the length correctly in mm units.

Please find the modified code:

        public Result Execute(ExternalCommandData cmdData, ref string msg, ElementSet elemSet)
        {
            UIApplication uiap = cmdData.Application;
            UIDocument uidoc = uiap.ActiveUIDocument;
            Document doc = uidoc.Document;


           View view = doc.ActiveView;
            XYZ startPoint = new XYZ(0, 0, 0);
            XYZ endPoint = new XYZ(UnitUtils.Convert(100, DisplayUnitType.DUT_MILLIMETERS, DisplayUnitType.DUT_DECIMAL_FEET), 0, 0);

            using (Transaction t = new Transaction(doc, "Creat Detail Line"))
            {
                t.Start();
                Line l1 = Line.CreateBound(startPoint, endPoint);
                doc.Create.NewDetailCurve(view, l1);
                t.Commit();
                TaskDialog.Show("Creat Detail Line", "Line was created");
            }

            return Result.Succeeded;
        }

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