a = TextBox1.Text
b = TextBox2.Text
c = TextBox3.Text
d = TextBox4.Text
e = TextBox5.Text
k = a * Sin(X / b) + c
Set swApp = _
Application.SldWorks

Set Part = swApp.ActiveDoc
boolstatus = Part.Extension.SelectByID2("草图1", "SKETCH", 0, 0, 0, False, 0, Nothing, 0)
Part.EditSketch
Part.ClearSelection2 True
boolstatus = Part.Extension.SelectByID2("Spline2", "SKETCHSEGMENT", 1.88304242471792E-02, 8.09688949697063E-03, -0.012484411658199, False, 0, Nothing, 0)
Dim equationCurve As Object
boolstatus = Part.Extension.SelectByID2("Spline2", "SKETCHSEGMENT", 1.88304242471792E-02, 8.09688949697063E-03, -0.012484411658199, False, 0, Nothing, 0)
Set equationCurve = Part.SelectionManager.GetSelectedObject5(1)
   boolstatus = equationCurve.SetEquationParameters2("", k, "", d, e, False, 0, 0, 0, True, True)
Part.ClearSelection2 True
Part.SketchManager.InsertSketch True

dim k as string
k=a & "*Sin(" & x & "/" & b & ")+" & c

'没看见对x的赋值