protected void btnExport_Click(object sender, EventArgs e)

    {

        string template = Server.MapPath("Notice.docx");

        Dictionary<string, string> dct = new Dictionary<string, string>()

            { { "today", DateTime.Today.ToString("yyyy-MM-dd") },

              { "name", txtName.Text },

              { "addr", txtAddr.Text },

              { "amount", txtAmount.Text } };

        Response.Clear();

        Response.ContentType = "application/octet-stream";

        Response.AddHeader("content-disposition", "attachment;filename=Notice.docx");

        Response.BinaryWrite(

            Darkthread.OpenXml.DocxHelper.MakeDocx(

                Server.MapPath("Notice.docx"), 

                dct)

        );

        Response.End();

    }

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using DocumentFormat.OpenXml.Packaging;

using System.IO;

namespace Darkthread.OpenXml

{

    /// <summary>

    /// Ver 1.0 By Jeffrey Lee, 2009-07-29

    /// </summary>

    public class DocxHelper

    {

        /// <summary>

        /// Replace the parser tags in docx document

        /// </summary>

        /// <param name="oxp">OpenXmlPart object</param>

        /// <param name="dct">Dictionary contains parser tags to replace</param>

        private static void parse(OpenXmlPart oxp, Dictionary<string, string> dct)

        {

            string xmlString = null;

            using (StreamReader sr = new StreamReader(oxp.GetStream()))

            { xmlString = sr.ReadToEnd(); }

            foreach (string key in dct.Keys)

                xmlString = xmlString.Replace("[$" + key + "$]", dct[key]);

            using (StreamWriter sw = new StreamWriter(oxp.GetStream(FileMode.Create)))

            { sw.Write(xmlString); }

        }

        /// <summary>

        /// Parse template file and replace all parser tags, return the binary content of

        /// new docx file.

        /// </summary>

        /// <param name="templateFile">template file path</param>

        /// <param name="dct">a Dictionary containing parser tags and values</param>

        /// <returns></returns>

        public static byte[] MakeDocx(string templateFile, Dictionary<string, string> dct)

        {

            string tempFile = Path.GetTempPath() + ".docx";

            File.Copy(templateFile, tempFile);

            using (WordprocessingDocument wd = WordprocessingDocument.Open(

                tempFile, true))

            {

                //Replace document body

                parse(wd.MainDocumentPart, dct);

                foreach (HeaderPart hp in wd.MainDocumentPart.HeaderParts)

                    parse(hp, dct);

                foreach (FooterPart fp in wd.MainDocumentPart.FooterParts)

                    parse(fp, dct);

            }

            byte[] buff = File.ReadAllBytes(tempFile);

            File.Delete(tempFile);

            return buff;

        }

    }

}