asp.net如何导出word

以前做的软件用户大多数都是要求导出格式为Excel,最近新接了个单子用户要求导出格式为Word,因为以前没做过，只能去为百度了，不过通过在网上学习发现跟Excel的导出也大同小异，现在将我所写的代码，贴到下面，希望能给有同样困惑的童鞋们带来帮助！

 if (gridViewReAmount.FocusedRowHandle >=0)//word的内容是从gridview中导出
            {
                DataRow row = gridViewReAmount.GetFocusedDataRow();
                //生成WORD程序对象和WORD文档对象
                Microsoft.Office.Interop.Word.Application appWord = new Microsoft.Office.Interop.Word.Application();
                Microsoft.Office.Interop.Word.Document doc = new Microsoft.Office.Interop.Word.Document();
                object oMissing = System.Reflection.Missing.Value;//这个是什么东西，我始终没搞明白-_-

                //打开模板文档，并指定doc的文档类型
                object objTemplate = System.Windows.Forms.Application.StartupPath + @"\告知单.doc";
                object objDocType = Microsoft.Office.Interop.Word.WdDocumentType.wdTypeDocument;
                doc = (Microsoft.Office.Interop.Word.Document)appWord.Documents.Add(ref objTemplate, ref oMissing, ref objDocType, ref oMissing);

                //获取模板中所有的书签
                string arrears = ((Convert.ToDouble(row["ContractAmount"].ToString()) - Convert.ToDouble(row["ReAmount"].ToString()))).ToString(".##");
                DateTime applydate = Convert.ToDateTime(row["ApplyDate"].ToString());
                string appdate = applydate.ToLongDateString().ToString();
                string promisedate1 = (Convert.ToDateTime(row["PromiseDate1"].ToString())).ToLongDateString().ToString();
                string promisereamount1 = ((Convert.ToDouble(row["PromiseReAmount1"].ToString()))).ToString(".##");
                double remaindays = (Convert.ToDateTime(row["PromiseDate1"].ToString()) - DateTime.Now).TotalDays;
                doc.Bookmarks["ReleaseDate"].Range.Text = DateTime.Now.ToShortDateString();
                doc.Bookmarks["Center"].Range.Text = row["Center"].ToString();
                doc.Bookmarks["Office"].Range.Text = row["Office"].ToString();
                doc.Bookmarks["Saler"].Range.Text = row["Saler"].ToString();
                doc.Bookmarks["ContractName"].Range.Text = row["ContractName"].ToString();
                doc.Bookmarks["ContractAmount"].Range.Text = (Convert.ToDouble(row["ContractAmount"].ToString())).ToString(".##");
                doc.Bookmarks["ReAmount"].Range.Text = (Convert.ToDouble(row["ReAmount"].ToString())).ToString(".##");
                doc.Bookmarks["Arrears"].Range.Text = arrears;
                doc.Bookmarks["ApplyDate"].Range.Text =appdate;
                doc.Bookmarks["WriteBack"].Range.Text = row["WriteBack"].ToString();
                doc.Bookmarks["PromiseDate1"].Range.Text = promisedate1;
                doc.Bookmarks["PromiseReAmount1"].Range.Text = promisereamount1;
                doc.Bookmarks["Remaindays"].Range.Text = remaindays.ToString("#");

                //第四步 生成word，将当前的文档对象另存为指定的路径，然后关闭doc对象。关闭应用程序
                saveFileDoc.FileName = "告知单" + "("+ row["Saler"].ToString() + DateTime.Now.ToShortDateString()+")";
                if (saveFileDoc.ShowDialog() == DialogResult.OK)
                {
                    object filename = saveFileDoc.FileName;
                    object miss = System.Reflection.Missing.Value;
                    doc.SaveAs(ref filename, ref miss, ref miss, ref miss, ref miss, ref miss, ref miss, ref miss, ref miss, ref miss, ref miss, ref miss, ref miss, ref miss, ref miss, ref miss);
                    object missingValue = Type.Missing;
                    object doNotSaveChanges = Microsoft.Office.Interop.Word.WdSaveOptions.wdDoNotSaveChanges;
                    //doc.Close();
                    doc.Close(ref doNotSaveChanges, ref missingValue, ref missingValue);
                    appWord.Application.Quit(ref miss, ref miss, ref miss);
                    doc = null;
                    appWord = null;
                    MessageBox.Show("生成成功！", "提示");
                }