Asp.net girdview 匯出.csv格式

 /// <summary>
        /// export to .csv format
        /// </summary>
        /// <param name="gv">gridview control</param>
        /// <param name="page">page</param>
        /// <param name="fileName">file name</param>
        public static void ImportToCSV(System.Web.UI.WebControls.GridView gv, System.Web.UI.Page page,int[] displayColumns, string fileName)
        {
            string defaultFileName = "input name.csv";
            if (string.IsNullOrEmpty(fileName))
            {
                fileName = defaultFileName;
            }
            StringBuilder sb = new StringBuilder();
            page.Response.AppendHeader("Content-Disposition", "attachment;filename=" + fileName);
            //page.Response.ContentType = "application/ms-excel";
            page.Response.Charset = "UTF-8";
            page.Response.ContentEncoding = System.Text.Encoding.UTF8;

            foreach (System.Web.UI.WebControls.GridViewRow row in gv.Rows)
            {
                if (row.RowType == System.Web.UI.WebControls.DataControlRowType.DataRow)
                {
                    for (int i = 0; i < displayColumns.Length; i++)
                    {
                        //&nbsp; has instead of string.empty when default value is string.empty in the cell of gridview, so replace it.
                        sb.Append("\"");
                        if (!row.Cells[displayColumns[i]].Text.Trim().Equals("&nbsp;"))
                        {
                            sb.Append(row.Cells[displayColumns[i]].Text.Trim());
                        }
                        sb.Append("\"");
                        if (i != displayColumns.Length - 1)
                        {
                            sb.Append(",");
                        }
                        else
                        {
                            sb.Append("\r\n");
                        }
                    }
                }
            }

            //輸出
            page.Response.Write(sb.ToString());
            page.Response.End();
        }