C#中怎么导出数据到Excel

public void CreateExcel1(DataSet ds, string typeid, string FileName)
    {
        HttpResponse resp = System.Web.HttpContext.Current.Response;

        resp.ContentEncoding = System.Text.Encoding.GetEncoding("GB2312");
        resp.AppendHeader("Content-Disposition", "attachment;filename=" + FileName);
        resp.Charset = "UTF-8";
        string colHeaders = "", ls_item = "";
        int i = 0;

        DataTable dt = ds.Tables[0];
        DataRow[] myRow = dt.Select("");
        if (typeid == "1")
        {

            colHeaders += "<table cellspacing="0" cellpadding="5" rules="all" border="1"> <tr >";
            for (i = 0; i < dt.Columns.Count - 1; i++)
                colHeaders += "<td>" + dt.Columns[i].Caption.ToString() + "</td>";
            colHeaders += "<td>" + dt.Columns[i].Caption.ToString() + "</td></tr>";
            resp.Write(colHeaders);
            foreach (DataRow row in myRow)
            {
                ls_item += "<tr>";
                for (i = 0; i < dt.Columns.Count - 1; i++)
                    ls_item += "<td >" + row[i].ToString().Replace("t", "") + "</td>";
                ls_item += "<td>" + row[i].ToString().Replace("t", "") + "</td></tr>";
                resp.Write(ls_item);
                ls_item = "";
            }
        }
        else
        {
            if (typeid == "2")
            {
                resp.Write(ds.GetXml());
            }
        }
        resp.End();
    }