Hi, I am working on C# script for API. 
I have created all feature on origin. I want to select surface without using coordinate position for trimming purpose.

My question:

Suppose, I have two profile surface too far from origin position and now I want to select this two surface for trimmingAPI Macros#Surfacing 

I have attached cad model 2025 version


using System;
using System.Runtime.InteropServices;
using System.Text.RegularExpressions;
using System.Threading;
using System.Reflection;
using SolidWorks.Interop.sldworks;
using SolidWorks.Interop.swconst;

namespace SurfaceSelectHelper
{
   class Program
   {
       // This event will be set by the external event handler when trim finishes
       // (Do NOT add the handler here if you said not to — handler must call Program.trimmedEvent.Set();)
       public static ManualResetEventSlim trimmedEvent = new ManualResetEventSlim(false);

       [STAThread]
       static void Main()
       {

           // Attach to running SolidWorks
           SldWorks swApp = (SldWorks)Marshal.GetActiveObject("SldWorks.Application");

           // Active part document
           ModelDoc2 swModel = (ModelDoc2)swApp.ActiveDoc;

           // ---- Surface 1 (Right Plane) ----
           // Select Right plane
           swModel.Extension.SelectByID2("Right plane", "PLANE", 0, 0, 0, false, 0, null, 0);

           // Insert sketch
           swModel.SketchManager.InsertSketch(true);

           // Create a line 01
           swModel.SketchManager.CreateLine(-0.068922, 0.023964, 0.0, 0.042733, 0.005543, 0.0);

           // Exit sketch
           swModel.SketchManager.InsertSketch(true);

           // Show Isometric view
           swModel.ShowNamedView2("*Isometric", (int)swStandardViews_e.swIsometricView);

           // Zoom to fit
           swModel.ViewZoomtofit2();

           // Extrude surface 01
           swModel.FeatureManager.FeatureExtruRefSurface3(
               true,       // Sd: single-ended
               false,      // Dir: flip direction (reverse)
               (int)swStartConditions_e.swStartSketchPlane,        // StartCond
               0,      // OffsetVal
               (int)swEndConditions_e.swEndCondBlind,      // T1 (termination type for end 1)
               (int)swEndConditions_e.swEndCondBlind,      // T2 (not used when Sd=true)
               0.06604,        // D1 -> depth (meters) for the (flipped) single end
               0,      // D2 (unused for single-ended)
               true, false, false, false,
               0, 0, false, false, false, false, false, false,
               false, false);

           // Clear previous selections
           swModel.ClearSelection2(true);

           // ---- Surface 2 (Right Plane) ----
           // Select Right plane
           swModel.Extension.SelectByID2("Right plane", "PLANE", 0, 0, 0, false, 0, null, 0);

           // Insert sketch
           swModel.SketchManager.InsertSketch(true);

           // Create a line 02
           swModel.SketchManager.CreateLine(0.0, 0.023059, 0.0, 0.0, -0.081662, 0.0);

           // Exit sketch
           swModel.SketchManager.InsertSketch(true);

           // --- WAIT here for external event-handler to signal trim finished ---
           // Wait up to 10 seconds (10000 ms). No if/else used; we capture the boolean result.
           bool signaled = trimmedEvent.Wait(10000);

           // Extrude surface 02
           swModel.FeatureManager.FeatureExtruRefSurface3(
               false,                          // Sd: single-ended
               false,                          // Dir: flip direction (reverse)
               (int)swStartConditions_e.swStartSketchPlane, // StartCond
               0,                             // OffsetVal
               (int)swEndConditions_e.swEndCondBlind,      // T1 (termination type for end 1)
               (int)swEndConditions_e.swEndCondBlind,      // T2 (not used when Sd=true)
               0.06604,                          // D1 -> depth (meters) for the (flipped) single end
               0.02,                             // D2 (unused for single-ended)
               true, false, false, false,
               0, 0, false, false, false, false, false, false,
               false, false);

           swModel.ClearSelection2(true);
           swModel.EditRebuild3();

           // Select second surface
           bool selByName = swModel.Extension.SelectByID2("Surface-Extrude2", "FACEBODY", 0, 0, 0, true, 0, null, 0);

           // --- Now do PreTrimSurface, select the target surface body and PostTrimSurface ---
           // Call PreTrimSurface (same boolean order as your VB sample)
           var preTrimStatus = swModel.FeatureManager.PreTrimSurface(false, true, false, true);

           // Select the surface body by coordinates(you provided these coordinates)
           // Note: use exact double values (scientific notation allowed)
           bool selResult = swModel.Extension.SelectByID2(
               "", "FACEBODY", 4.76514312435938E-02, 8.84694633197114E-03, -2.27068272785118E-02, true, 0, null, 0);

           // Call PostTrimSurface and capture returned Feature object
           object myFeature = swModel.FeatureManager.PostTrimSurface(true);

           // Clear selection and rebuild to update model
           swModel.ClearSelection2(true);
           swModel.EditRebuild3();
       }
   }
}