using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Runtime.InteropServices;
using Microsoft.Office.Interop.Excel;
//Office 命名空間
namespace OfficeToPdf
{
  //excel 類
  class ExcelConverter
  {
    //構(gòu)造函數(shù)
    public ExcelConverter()
    { }
    /// <summary>
    /// 轉(zhuǎn)換excel 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.Excel.Application lobjExcelApp = null;      
      Microsoft.Office.Interop.Excel.Workbooks lobjExcelWorkBooks = null;
      Microsoft.Office.Interop.Excel.Workbook lobjExcelWorkBook = null;
      string lstrTemp = string.Empty;
      object lobjMissing = System.Reflection.Missing.Value;
      try
      {
        lobjExcelApp = new Microsoft.Office.Interop.Excel.Application();
        lobjExcelApp.Visible = true;
        lobjExcelWorkBooks = lobjExcelApp.Workbooks;
        lobjExcelWorkBook = lobjExcelWorkBooks.Open(_lstrInputFile, true, true, lobjMissing, lobjMissing, lobjMissing, true,
          lobjMissing, lobjMissing, lobjMissing, lobjMissing, lobjMissing, false, lobjMissing, lobjMissing);
        //Microsoft.Office.Interop.Excel 12.0.0.0之后才有這函數(shù)      
        lstrTemp = System.IO.Path.GetTempPath() + Guid.NewGuid().ToString() + ".xls" + (lobjExcelWorkBook.HasVBProject ? 'm' : 'x');
        //lstrTemp = System.IO.Path.GetTempPath() + Guid.NewGuid().ToString() + ".xls";
        lobjExcelWorkBook.SaveAs(lstrTemp, Microsoft.Office.Interop.Excel.XlFileFormat.xlExcel4Workbook, Type.Missing, Type.Missing, Type.Missing, false, Microsoft.Office.Interop.Excel.XlSaveAsAccessMode.xlNoChange, Type.Missing,
          false, Type.Missing, Type.Missing, Type.Missing);
        //輸出為PDF 第一個選項指定轉(zhuǎn)出為PDF,還可以指定為XPS格式
        lobjExcelWorkBook.ExportAsFixedFormat(Microsoft.Office.Interop.Excel.XlFixedFormatType.xlTypePDF, _lstrOutFile, Microsoft.Office.Interop.Excel.XlFixedFormatQuality.xlQualityStandard, Type.Missing, false, Type.Missing, Type.Missing, false, Type.Missing);
        lobjExcelWorkBooks.Close();
        lobjExcelApp.Quit();
      }
      catch (Exception ex)
      {
        //其他日志操作；
        return false;
      }
      finally {
        if (lobjExcelWorkBook != null)
        {
          lobjExcelWorkBook.Close(Type.Missing,Type.Missing,Type.Missing);
          Marshal.ReleaseComObject(lobjExcelWorkBook);
          lobjExcelWorkBook = null;
        }
        if(lobjExcelWorkBooks != null)
        {
          lobjExcelWorkBooks.Close();
          Marshal.ReleaseComObject(lobjExcelWorkBooks);
          lobjExcelWorkBooks = null;
        }
        if(lobjExcelApp != null)
        {
          lobjExcelApp.Quit();
          Marshal.ReleaseComObject(lobjExcelApp);
          lobjExcelApp = null;
        } 
        //主動激活垃圾回收器，主要是避免超大批量轉(zhuǎn)文檔時，內(nèi)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;
    }
  }
}