利用wps的API将word、excel、ppt转换为pdf

第一步：本机安装WPS（我安装的时WPS2013）

第二步：添加引用，在COM中以Kingsoft开头的

注意：引用添加后，wps对应的时doc格式；wpp对应的是ppt格式；et对应的是excel格式

/// <summary>
        /// 转换DOC到PDF
        /// </summary>
        /// <param name="wpsFilename">原始文件</param>
        /// <param name="pdfFilename">转换后pdf文件</param>
        private void ConvertDocToPdf(string wpsFilename, string pdfFilename)
        {
            WPS.Application wps = new WPS.Application();
            try
            {               
                if (wpsFilename == null) { throw new ArgumentNullException("wpsFilename"); }
                //保存路径为空时，保存在原始文件目录
                if (pdfFilename == "")
                {
                    pdfFilename = Path.ChangeExtension(wpsFilename, "pdf");
                }
                //忽略警告提示
                wps.DisplayAlerts = WPS.WpsAlertLevel.wpsAlertsNone;
                Document doc = wps.Documents.Open(wpsFilename,Visible: true, NoEncodingDialog: true);
                doc.ExportPdf(pdfFilename);
                doc.Close();            
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message.ToString());
            }
            finally
            {
                //无论是否成功，都退出
                if (wps != null) 
                {
                    wps.Terminate();
                    //强制关闭所有wps进程
                    System.Diagnostics.Process[] process = System.Diagnostics.Process.GetProcessesByName("wps");
                    foreach (System.Diagnostics.Process prtemp in process)
                    {
                        prtemp.Kill();
                    }
                }
            }
        }

        /// <summary>
        /// 转换EXCEL到PDF
        /// </summary>
        /// <param name="wpsFilename">原始文件</param>
        /// <param name="pdfFilename">转换后pdf文件</param>
        private void ConvertExcelToPdf(string wpsFilename, string pdfFilename)
        {
            ET.Application eps = new ET.Application();
            try
            {
                if (wpsFilename == null) { throw new ArgumentNullException("wpsFilename"); }
                //保存路径为空时，保存在原始文件目录
                if (pdfFilename == "")
                {
                    pdfFilename = Path.ChangeExtension(wpsFilename, "pdf");
                }
                //忽略警告提示
                eps.DisplayAlerts = false;
                eps.Workbooks.Open(wpsFilename);
                eps.ActiveWorkbook.ExportPdf(pdfFilename);
                eps.ActiveWorkbook.Close();              
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message.ToString());
            }
            finally
            {
                //无论是否成功，都退出
                if (eps != null) 
                {
                    eps.Quit();
                    eps.Terminate();
                    //强制关闭所有et进程
                    System.Diagnostics.Process[] process = System.Diagnostics.Process.GetProcessesByName("et");
                    foreach (System.Diagnostics.Process prtemp in process)
                    {
                        prtemp.Kill();
                    }
                }
            } 
        }

        /// <summary>
        /// 转换PPT到PDF
        /// </summary>
        /// <param name="wpsFilename">原始文件</param>
        /// <param name="pdfFilename">转换后pdf文件</param>
        private void ConvertPptToPdf(string wpsFilename, string pdfFilename)
        {
            WPP.Application pps = new WPP.Application();

            try
            {
                if (wpsFilename == null) { throw new ArgumentNullException("wpsFilename"); }
                //保存路径为空时，保存在原始文件目录
                if (pdfFilename == "")
                {
                    pdfFilename = Path.ChangeExtension(wpsFilename, "pdf");
                }
                //忽略警告提示 此处无法设置，原因不清楚！
                //pps.DisplayAlerts = WPP.WpAlertLevel.wpAlertsAll;
                //应用程序不可见
                //pps.Visible = KSO.KsoTriState.ksoFalse;
                
                pps.Presentations.Open(wpsFilename);
                pps.ActivePresentation.ExportPdf(pdfFilename);
                pps.ActivePresentation.Close();
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message.ToString());
            }
            finally
            {
                //无论是否成功，都退出
                if (pps != null)
                {                   
                    pps.Quit();
                    //强制关闭所有wpp进程
                    System.Diagnostics.Process[] process = System.Diagnostics.Process.GetProcessesByName("wpp");
                    foreach (System.Diagnostics.Process prtemp in process)
                    {
                        prtemp.Kill(); 
                    }
                }
            } 
        }