using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Xml.Linq;
using PowerPoint = Microsoft.Office.Interop.PowerPoint;
using Office = Microsoft.Office.Core;

namespace VSTO
{
    public partial class ThisAddIn
    {
        private void ThisAddIn_Startup(object sender, System.EventArgs e)
        {
            //Open ppt document
            PowerPoint.Presentation ppt = Application.Presentations.Open("../../Sample.pptx");

            //Fit to page
            ppt.PrintOptions.FitToPage = Office.MsoTriState.msoTrue;

            //Print
            ppt.PrintOut(1, ppt.Slides.Count, "", 0);
        }

        private void ThisAddIn_Shutdown(object sender, System.EventArgs e)
        {
        }

        #region VSTO generated code

        /// <summary>
        /// Required method for Designer support - do not modify
        /// the contents of this method with the code editor.
        /// </summary>
        private void InternalStartup()
        {
            this.Startup += new System.EventHandler(ThisAddIn_Startup);
            this.Shutdown += new System.EventHandler(ThisAddIn_Shutdown);
        }
        
        #endregion
    }
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Spire.Presentation;
using System.Drawing.Printing;

namespace Spire.Presentation
{
    class Program
    {
        static void Main(string[] args)
        {
            //Load ppt document
            Presentation ppt = new Presentation();
            ppt.LoadFromFile("../../Sample.pptx");

            //Printer setting
            PrinterSettings printerSettings = new PrinterSettings();
            printerSettings.DefaultPageSettings.Margins.Top =10;

            //Print
            ppt.Print(printerSettings);
        }
    }
}