MicroStation supports a variety of element types, which can generally be categorized into graphical and non-graphical elements. In this section, we will focus on creating graphical elements using the MicroStation object model with-in an Add-in.
Understanding how these elements are created is an important step in developing custom MicroStation applications. The following diagram illustrates the overall architecture of a MicroStation Add-in and highlights the key APIs involved. When working with graphical elements, developers primarily interact with the DgnPlatformNET library, which provides the classes and methods required to create, modify, and manage elements within a design file.
To gain a deeper understanding of the MicroStation object model, refer to the SDK documentation available in the following folder:
C:\Program Files\Bentley\MicroStation2026SDK\Documentation\
Another useful way to explore the MicroStation object model is through Visual Studio's Object Browser. After adding references to the required MicroStation assemblies, you can browse the complete object hierarchy, inspect available classes and methods, and better understand API relationships.
As shown in the following figure, the Object Browser can be opened by selecting View > Object Browser from the Visual Studio menu.
With a basic understanding of the MicroStation object model and graphical elements, we are now ready to start creating graphical elements in a DGN model.
In the following sections, we will walk through the process step by step, demonstrating how to create and add elements programmatically within a MicroStation Add-in.
- Create a new Project
Begin by creating a new Add-in project by following the steps described in the previous section, Building a Simple Add-in Application, name the new project csAddins2
If you have already created a Visual Studio project template from the previous section, you can use that template to quickly generate a new project. Simply create a new project from the template and assign it the name csAddins2.
- Create a new C# Class
- Right-click csAddins2 in the Solution Explorer and select Add > New Item.
- In the pop-up form, select Class under C# Items, enter the file name as CreateElement.cs.
- Click the Add button to create a C# Class file.
- Edit CreateElement.cs file
Copy and paste the following code into CreateElement.cs file.
using Bentley.DgnPlatformNET;
using Bentley.DgnPlatformNET.Elements;
using Bentley.GeometryNET;
using Bentley.MstnPlatformNET;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using BIM = Bentley.Interop.MicroStationDGN;
namespace csAddins2
{
class CreateElement
{
static double UorPerMas = Session.Instance.GetActiveDgnModel().GetModelInfo().UorPerMaster;
public static void LineAndLineString1()
{
BIM.Application app = Bentley.MstnPlatformNET.InteropServices.Utilities.ComApp;
BIM.Point3d ptStart = app.Point3dZero();
BIM.Point3d ptEnd = ptStart;
ptStart.X = 10;
BIM.LineElement lineEle = app.CreateLineElement2(null, ref ptStart, ref ptEnd);
lineEle.Color = 0; lineEle.LineWeight = 2;
app.ActiveModelReference.AddElement(lineEle);
}
public static void LineAndLineString2()
{
DgnModel dgnModel = Session.Instance.GetActiveDgnModel();
ModelInfo modelInfo = dgnModel.GetModelInfo();
DSegment3d seg = new DSegment3d ( 0 * UorPerMas, 5 * UorPerMas, 0 * UorPerMas,
10 * UorPerMas, 10 * UorPerMas, 0 * UorPerMas);
LineElement lineEle = new LineElement(dgnModel, null, seg);
lineEle.AddToModel();
DPoint3d[] ptArr = new DPoint3d[5];
ptArr[0] = new DPoint3d(15 * UorPerMas, 10 * UorPerMas, 0 * UorPerMas);
ptArr[1] = new DPoint3d(16 * UorPerMas, 12 * UorPerMas, 0 * UorPerMas);
ptArr[2] = new DPoint3d(18 * UorPerMas, 8 * UorPerMas, 0 * UorPerMas);
ptArr[3] = new DPoint3d(20 * UorPerMas, 12 * UorPerMas, 0 * UorPerMas);
ptArr[4] = new DPoint3d(21 * UorPerMas, 10 * UorPerMas, 0 * UorPerMas);
LineStringElement lineStrEle = new LineStringElement(dgnModel, null, ptArr);
lineStrEle.AddToModel();
}
public static void LineAndLineString3()
{
DgnModel dgnModel = Session.Instance.GetActiveDgnModel();
ModelInfo modelInfo = dgnModel.GetModelInfo();
DPoint3d[] ptArr = new DPoint3d[5];
ptArr[0] = new DPoint3d(0 * UorPerMas, 10 * UorPerMas, 0 * UorPerMas);
ptArr[1] = new DPoint3d(1 * UorPerMas, 12 * UorPerMas, 0 * UorPerMas);
ptArr[2] = new DPoint3d(3 * UorPerMas, 8 * UorPerMas, 0 * UorPerMas);
ptArr[3] = new DPoint3d(5 * UorPerMas, 12 * UorPerMas, 0 * UorPerMas);
ptArr[4] = new DPoint3d(6 * UorPerMas, 10 * UorPerMas, 0 * UorPerMas);
CurvePrimitive curPri = CurvePrimitive.CreateLineString(ptArr);
Element ele = DraftingElementSchema.ToElement(dgnModel, curPri, null);
ele.AddToModel();
}
public static void ShapeAndComplexShape()
{
DgnModel dgnModel = Session.Instance.GetActiveDgnModel();
DPoint3d[] ptArr = new DPoint3d[6];
ptArr[0] = new DPoint3d(0 * UorPerMas, -6 * UorPerMas, 0 * UorPerMas);
ptArr[1] = new DPoint3d(0 * UorPerMas, -2 * UorPerMas, 0 * UorPerMas);
ptArr[2] = new DPoint3d(2 * UorPerMas, -2 * UorPerMas, 0 * UorPerMas);
ptArr[3] = new DPoint3d(2 * UorPerMas, -4 * UorPerMas, 0 * UorPerMas);
ptArr[4] = new DPoint3d(4 * UorPerMas, -4 * UorPerMas, 0 * UorPerMas);
ptArr[5] = new DPoint3d(4 * UorPerMas, -6 * UorPerMas, 0 * UorPerMas);
ShapeElement shapeEle = new ShapeElement(dgnModel, null, ptArr);
ElementPropertiesSetter elePropSet = new ElementPropertiesSetter();
elePropSet.SetColor(0);
elePropSet.SetWeight(2);
elePropSet.Apply(shapeEle);
shapeEle.AddToModel();
for (int i = 0; i < 6; i++)
ptArr[i].X += 5 * UorPerMas;
CurvePrimitive curvePri = CurvePrimitive.CreateLineString(ptArr);
CurveVector curVec = CurveVector.Create(CurveVector.BoundaryType.Outer);
curVec.Add(curvePri);
ptArr[2].Y = -8;
DEllipse3d ellipse = new DEllipse3d();
if (DEllipse3d.TryCircularArcFromCenterStartEnd(ptArr[2], ptArr[5], ptArr[0], out ellipse))
{
curvePri = CurvePrimitive.CreateArc(ellipse);
curVec.Add(curvePri);
Element eleTemp = DraftingElementSchema.ToElement(dgnModel, curVec, null);
eleTemp.AddToModel();
elePropSet.SetColor(1);
elePropSet.SetWeight(2);
elePropSet.Apply(eleTemp);
eleTemp.AddToModel();
}
}
public static void TextString()
{
DgnFile dgnFile = Session.Instance.GetActiveDgnFile();
DgnModel dgnModel = Session.Instance.GetActiveDgnModel();
TextBlockProperties txtBlockProp = new TextBlockProperties(dgnModel);
txtBlockProp.IsViewIndependent = true;
ParagraphProperties paraProp = new ParagraphProperties(dgnModel);
DgnTextStyle txtStyle = DgnTextStyle.GetSettings(dgnFile);
RunProperties runProp = new RunProperties(txtStyle, dgnModel);
TextBlock txtBlock = new TextBlock(txtBlockProp, paraProp, runProp, dgnModel);
txtBlock.AppendText("Hello from C# Addin");
TextHandlerBase txtHandlerBase = TextHandlerBase.CreateElement(null, txtBlock);
DTransform3d trans = DTransform3d.Identity;
trans.Translation = new DVector3d(6 * UorPerMas, 2 * UorPerMas, 3 * UorPerMas); //UOR unit
TransformInfo transInfo = new TransformInfo(trans);
txtHandlerBase.ApplyTransform(transInfo);
txtHandlerBase.AddToModel();
}
public static void Cell()
{
DgnModel dgnModel = Session.Instance.GetActiveDgnModel();
DPoint3d[] ptArr = new DPoint3d[5];
ptArr[0] = new DPoint3d(-15 * UorPerMas, -5 * UorPerMas, 0 * UorPerMas);
ptArr[1] = new DPoint3d(-15 * UorPerMas, 5 * UorPerMas, 0 * UorPerMas);
ptArr[2] = new DPoint3d(-5 * UorPerMas, 5 * UorPerMas, 0 * UorPerMas);
ptArr[3] = new DPoint3d(-5 * UorPerMas, -5 * UorPerMas, 0 * UorPerMas);
ptArr[4] = new DPoint3d(-15 * UorPerMas, -5 * UorPerMas, 0 * UorPerMas);
ShapeElement shapeEle = new ShapeElement(dgnModel, null, ptArr);
DPlacementZX dPlaceZX = DPlacementZX.Identity;
dPlaceZX.Origin = new DPoint3d(-10 * UorPerMas, 0, 0);
DEllipse3d ellipse = new DEllipse3d (dPlaceZX, 5 * UorPerMas, 5 * UorPerMas,
Angle.Zero, Angle.TWOPI);
EllipseElement elliEle = new EllipseElement(dgnModel, null, ellipse);
List<Element> listEle = new List<Element>();
listEle.Add(shapeEle);
listEle.Add(elliEle);
DPoint3d ptOri = new DPoint3d();
DMatrix3d rMatrix = DMatrix3d.Identity;
DPoint3d ptScale = new DPoint3d(1, 1, 1);
CellHeaderElement cellHeaderEle = new CellHeaderElement(dgnModel, "CellElementSample", ptOri,
rMatrix, listEle);
cellHeaderEle.AddToModel();
}
public static void Dimension()
{
DgnFile dgnFile = Session.Instance.GetActiveDgnFile();
DgnModel dgnModel = Session.Instance.GetActiveDgnModel();
double uorPerMast = dgnModel.GetModelInfo().UorPerMaster;
DimensionStyle dimStyle = new DimensionStyle("DimStyle", dgnFile);
dimStyle.SetBooleanProp(true, DimStyleProp.Placement_UseStyleAnnotationScale_BOOLINT);
dimStyle.SetDoubleProp(1, DimStyleProp.Placement_AnnotationScale_DOUBLE);
dimStyle.SetBooleanProp(true, DimStyleProp.Text_OverrideHeight_BOOLINT);
dimStyle.SetDistanceProp(0.5 * uorPerMast, DimStyleProp.Text_Height_DISTANCE, dgnModel);
dimStyle.SetBooleanProp(true, DimStyleProp.Text_OverrideWidth_BOOLINT);
dimStyle.SetDistanceProp(0.4 * uorPerMast, DimStyleProp.Text_Width_DISTANCE, dgnModel);
dimStyle.SetBooleanProp(true, DimStyleProp.General_UseMinLeader_BOOLINT);
dimStyle.SetDoubleProp(0.01, DimStyleProp.Terminator_MinLeader_DOUBLE);
dimStyle.SetBooleanProp(true, DimStyleProp.Value_AngleMeasure_BOOLINT);
dimStyle.SetAccuracyProp ((byte)AnglePrecision.Use1Place,
DimStyleProp.Value_AnglePrecision_INTEGER);
int alignInt = (int)DimStyleProp_General_Alignment.True;
StatusInt status = dimStyle.SetIntegerProp(alignInt, DimStyleProp.General_Alignment_INTEGER);
int valueOut;
dimStyle.GetIntegerProp(out valueOut, DimStyleProp.General_Alignment_INTEGER);
DgnTextStyle textStyle = new DgnTextStyle("TestStyle", dgnFile);
LevelId lvlId = Settings.GetLevelIdFromName("Default");
CreateDimensionCallbacks callbacks = new CreateDimensionCallbacks(dimStyle, textStyle,
new Symbology(),
lvlId, null);
DimensionElement dimEle = new DimensionElement(dgnModel, callbacks, DimensionType.SizeArrow);
if (dimEle.IsValid)
{
DPoint3d pt1 = DPoint3d.Zero, pt2 = DPoint3d.FromXY(uorPerMast * 10, uorPerMast * 0);
dimEle.InsertPoint(pt1, null, dimStyle, -1);
dimEle.InsertPoint(pt2, null, dimStyle, -1);
dimEle.SetHeight(uorPerMast);
DMatrix3d rMatrix = DMatrix3d.Identity;
dimEle.SetRotationMatrix(rMatrix);
dimEle.AddToModel();
}
}
public static void BsplineCurve()
{
DgnModel dgnModel = Session.Instance.GetActiveDgnModel();
DPoint3d[] ptArr = new DPoint3d[5];
ptArr[0] = new DPoint3d(0 * UorPerMas, 25 * UorPerMas, 0 * UorPerMas);
ptArr[1] = new DPoint3d(5 * UorPerMas, 35 * UorPerMas, 0 * UorPerMas);
ptArr[2] = new DPoint3d(10 * UorPerMas, 25 * UorPerMas, 0 * UorPerMas);
ptArr[3] = new DPoint3d(15 * UorPerMas, 35 * UorPerMas, 0 * UorPerMas);
ptArr[4] = new DPoint3d(20 * UorPerMas, 25 * UorPerMas, 0 * UorPerMas);
MSBsplineCurve msBsplineCurve = MSBsplineCurve.CreateFromPoles(ptArr, null, null, 3, false, true);
CurvePrimitive curvePri = CurvePrimitive.CreateBsplineCurve(msBsplineCurve);
Element ele = DraftingElementSchema.ToElement(dgnModel, curvePri, null);
ele.AddToModel();
}
public static void Cone()
{
DgnModel dgnModel = Session.Instance.GetActiveDgnModel();
DPoint3d ptTop = new DPoint3d(2 * UorPerMas, -15 * UorPerMas, 0 * UorPerMas);
DPoint3d ptBottom = new DPoint3d(2 * UorPerMas, -15 * UorPerMas, 3 * UorPerMas);
DMatrix3d rMatrix = DMatrix3d.Identity;
ConeElement coneEle = new ConeElement(dgnModel, null, 2 * UorPerMas, 1 * UorPerMas,
ptTop, ptBottom, rMatrix, true);
coneEle.AddToModel();
}
}
//Used By Dimension
class CreateDimensionCallbacks : DimensionCreateData
{
private DimensionStyle m_dimStyle;
private DgnTextStyle m_textStyle;
private Symbology m_symbology;
private LevelId m_levelId;
private DirectionFormatter m_directionFormatter;
public CreateDimensionCallbacks(DimensionStyle dimStyle, DgnTextStyle textStyle, Symbology symb,
LevelId levelId, DirectionFormatter formatter)
{
m_dimStyle = dimStyle;
m_textStyle = textStyle;
m_symbology = symb;
m_levelId = levelId;
m_directionFormatter = formatter;
}
public override DimensionStyle GetDimensionStyle()
{
return m_dimStyle;
}
public override DgnTextStyle GetTextStyle()
{
return m_textStyle;
}
public override Symbology GetSymbology()
{
return m_symbology;
}
public override LevelId GetLevelId()
{
return m_levelId;
}
public override int GetViewNumber()
{
return 0;
}
public override DMatrix3d GetDimensionRotation()
{
return DMatrix3d.Identity;
}
public override DMatrix3d GetViewRotation()
{
return DMatrix3d.Identity;
}
public override DirectionFormatter GetDirectionFormatter()
{
return m_directionFormatter;
}
}
}
- Modify MyAddins.cs file
Open the MyAddins.cs file and modify it as follows:
protected override int Run(string[] commandLine)
{
CreateElement.LineAndLineString1();
CreateElement.LineAndLineString2();
CreateElement.LineAndLineString3();
CreateElement.ShapeAndComplexShape();
CreateElement.TextString();
CreateElement.Cell();
CreateElement.Dimension();
CreateElement.BsplineCurve();
CreateElement.Cone();
return 0;
}
- Build Solution
Under menus, select Build > Build Solution to compile the solution.
- Run your Add-in program
- Launch/Open MicroStation, open the “key-in” window (or apply the F9 shortcut)
- Key-in “mdl load csAddins2” in the input field and press Enter.
- Graphical elements are successfully created and added to the active model.
You can download the source code for this wiki here.