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Create Equation-driven Curve (C#)

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

// Preconditions:  Open a part document.
// 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,
//    a cosine curve is created, and the number of points in the
//    spline is reduced.
using Microsoft.VisualBasic;
using System;
using System.Collections;
using System.Collections.Generic;
using System.Data;
using System.Diagnostics;
using SolidWorks.Interop.sldworks;
using SolidWorks.Interop.swconst;
using System.Runtime.InteropServices;
namespace SimplifySketchSpline_CSharp.csproj
partial class SolidWorksMacro

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 = (
            swExt = swModel.Extension;
            swSelMgr = (

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

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


SketchSpline skSpline = default(SketchSpline);
            skSpline = (
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);

// Reduce the number of points in the spline



public SldWorks swApp;


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