Using ActiveX Controls in Excel with C#. For more details: https://kb.aspose.com/cells/net/using-activex-controls-in-excel-with-csharp/

Using ActiveX Controls in Excel with C#.cs

using Aspose.Cells;
using Aspose.Cells.Drawing;
using Aspose.Cells.Drawing.ActiveXControls;

class Program
{
    static void Main(string[] args)
    {
        new License().SetLicense("License.lic");

        // Create workbook object
        Workbook wb = new Workbook();

        // Access first worksheet
        Worksheet sheet = wb.Worksheets[0];

        // Add Command Button ActiveX Control inside the Shape Collection
        Shape s = sheet.Shapes.AddActiveXControl(ControlType.CommandButton, 4, 0, 4, 0, 100, 30);

        // Access the ActiveX control object and set its linked cell property
        ActiveXControl c = s.ActiveXControl;
        c.LinkedCell = "A1";

        // Add Toggle Button ActiveX Control inside the Shape Collection
        Shape s1 = sheet.Shapes.AddActiveXControl(ControlType.ComboBox, 16, 0, 4, 0, 100, 30);

        // Access the ActiveX control object and set its linked cell property
        ActiveXControl c1 = s1.ActiveXControl;
        c1.LinkedCell = "A4";
        ComboBoxActiveXControl comboControl = (ComboBoxActiveXControl)c1;
        comboControl.Value = "A sample value for the ComboBox";

        // Save the workbook
        wb.Save("Combo box with original value.xlsx");

        foreach (var shape in sheet.Shapes)
        {
            // Access specific ActiveX Control and set its value
            if (shape.ActiveXControl != null)
            {
                // Access Shape ActiveX Control
                ActiveXControl control = shape.ActiveXControl;

                // Check for the target type
                if (control.Type == ControlType.ComboBox)
                {
                    // Type cast ActiveXControl into ComboBoxActiveXControl and change its value
                    ComboBoxActiveXControl comboBoxActiveX = (ComboBoxActiveXControl)control;
                    comboBoxActiveX.Value = "A new value for the ComboBox";
                }
            }
        }

        // Save the workbook in xlsx format
        wb.Save("AddActiveXControls_out.xlsx", SaveFormat.Xlsx);
    }
}