using System;using System.Collections.Generic;using System.IO;using System.Linq;using System.Text;using System.Runtime.InteropServices;using Microsoft.Office.Interop.PowerPoint;//Office 命名空間namespace OfficeToPdf{  //excel 類  class PowerPointConverter  {    //構造函數    public PowerPointConverter()    { }    /// <summary>    /// 轉換PowerPoint 成PDF文檔    /// </summary>    /// <param name="_lstrInputFile">原文件路徑</param>    /// <param name="_lstrOutFile">pdf文件輸出路徑</param>    /// <returns>true 成功</returns>    public bool ConverterToPdf(string _lstrInputFile, string _lstrOutFile)    {      Microsoft.Office.Interop.PowerPoint.Application lobjPowerPointApp = null;      Microsoft.Office.Interop.PowerPoint.Presentation lobjppt = null;      object lobjMissing = System.Reflection.Missing.Value;      object lobjSaveChanges = null;      try      {        lobjPowerPointApp = new Microsoft.Office.Interop.PowerPoint.Application();        lobjppt = lobjPowerPointApp.Presentations.Open(_lstrInputFile, MSCore.MsoTriState.msoTrue, MSCore.MsoTriState.msoFalse, MSCore.MsoTriState.msoFalse);        lobjppt.SaveAs(_lstrOutFile, PpSaveAsFileType.ppSaveAsPDF, MSCore.MsoTriState.msoCTrue);             }      catch (Exception ex)      {        //其他日志操作；        return false;      }      finally      {        if (lobjppt != null)        {          lobjppt.Close();          Marshal.ReleaseComObject(lobjppt);          lobjppt = null;        }        if (lobjPowerPointApp != null)        {          lobjPowerPointApp.Quit();          Marshal.ReleaseComObject(lobjPowerPointApp);          lobjPowerPointApp = null;        }        //主動激活垃圾回收器，主要是避免超大批量轉文檔時，內存占用過多，而垃圾回收器并不是時刻都在運行！        GC.Collect();        GC.WaitForPendingFinalizers();      }      return true;    }  }}