using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Runtime.InteropServices;
using Microsoft.Office.Interop.Word;
//Office 命名空間
namespace OfficeToPdf
{
  //excel 類
  class WordConverter
  {
    //構造函數
    public WordConverter()
    { }
    /// <summary>
    /// 轉換word 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.Word.Application lobjWordApp = null;
      Document objDoc = null;
      object lobjMissing = System.Reflection.Missing.Value;
      object lobjSaveChanges = null;
      try
      {
        Object lobjFileName = (Object)_lstrInputFile;
        objDoc = lobjWordApp.Documents.Open(ref lobjFileName, ref lobjMissing, ref lobjMissing,
          ref lobjMissing, ref lobjMissing, ref lobjMissing, ref lobjMissing, ref lobjMissing, ref lobjMissing, ref lobjMissing,
          ref lobjMissing, ref lobjMissing, ref lobjMissing, ref lobjMissing, ref lobjMissing, ref lobjMissing);
        objDoc.Activate();
        Object lobjOutPutFileName = (Object)_lstrOutFile;
        object lobjFileFormat = WdSaveFormat.wdFormatPDF; //保存格式為PDF
        objDoc.SaveAs(ref lobjOutPutFileName,ref lobjFileFormat, ref lobjMissing, ref lobjMissing, ref lobjMissing, ref lobjMissing,
          ref lobjMissing, ref lobjMissing, ref lobjMissing, ref lobjMissing, ref lobjMissing, ref lobjMissing, ref lobjMissing,
          ref lobjMissing, ref lobjMissing, ref lobjMissing);
        lobjSaveChanges = WdSaveOptions.wdDoNotSaveChanges;
        ((_Document)objDoc).Close(ref lobjSaveChanges, ref lobjMissing, ref lobjMissing);
        objDoc = null;
        ((_Application)lobjWordApp).Quit(ref lobjSaveChanges, ref lobjMissing, ref lobjMissing);
        lobjWordApp = null;
      }
      catch (Exception ex)
      {
        //其他日志操作；
        return false;
      }
      finally
      {
        if (objDoc != null)
        {
          ((_Document)objDoc).Close(ref lobjSaveChanges, ref lobjMissing, ref lobjMissing);
          Marshal.ReleaseComObject(objDoc);
          objDoc = null;
        }
        if (lobjWordApp != null)
        {
          ((_Application)lobjWordApp).Quit(ref lobjSaveChanges, ref lobjMissing, ref lobjMissing);
          Marshal.ReleaseComObject(lobjWordApp);
          lobjWordApp = 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;
    }
  }
}