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Create Equation-driven Curve (C#)

This example shows how to create and modify an equation-driven curve.


// Preconditions:  Part document is open in SolidWorks


// Postconditions:

// 1. A 2D sketch is created, and an equation spline of a

//    sine curve is created.  

// 2. After the break point, the curve is edited

//    and a cosine curve is created.


using SolidWorks.Interop.sldworks;

using SolidWorks.Interop.swconst;

using System;

using System.Diagnostics;

namespace ExampleCS.csproj


    partial class SolidWorksMacro


        #region Macro Variables

        ModelDoc2 swModel;

        ModelDocExtension swExt;

        SelectionMgr swSelMgr;

        bool boolstatus;

        string y;

        double r1;

        double r2;

        bool rad;

        double ang;

        double xOff;

        double yOff;

        bool LockStart;

        bool LockEnd;


        public void Main()


            swModel = swApp.ActiveDoc as ModelDoc2;

            swExt = swModel.Extension;

            swSelMgr = swModel.SelectionManager as SelectionMgr;

            boolstatus = swExt.SelectByID2("Front Plane", "PLANE", 0, 0, 0, false, 0, null, 0);



            SketchSegment skSegment;

            skSegment = swModel.SketchManager.CreateEquationSpline2("sin(x)", "", "", "0", "6.28", false, 0, 0.002, 0.002, false, false) as SketchSegment;



            SketchSpline skSpline;

            skSpline = skSegment as SketchSpline;

            skSpline.GetEquationParameters(out y, out r1, out r2, out rad, out ang, out xOff, out yOff, out LockStart, out LockEnd);

            Debug.Print("y: " + y);

            Debug.Print("range start: " + r1);

            Debug.Print("range end: " + r2);

            Debug.Print("radian?: " + rad);

            Debug.Print("ang offset: " + ang);

            Debug.Print("x offset: " + xOff);

            Debug.Print("y offset: " + yOff);

            Debug.Print("Lock start: " + LockStart);

            Debug.Print("Lock end: " + LockEnd);


            //Change spline to a cosine curve

            y = "cos(x)";

            skSpline.SetEquationParameters(y, r1, r2, rad, ang, xOff, yOff, LockStart,LockEnd);


        /// <summary>

        /// The SldWorks swApp variable is pre-assigned for you.

        /// </summary>

        public SldWorks swApp;



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