Create Xml,Csv,Zip files from dataset in asp.net

For Xml

protected void Button5_Click(object sender, EventArgs e)
    {

    int _count = ListSeCh.Items.Count;
        if (_count != 0)
        {
               DataTable dtTemp = new DataTable();
              dtTemp.Columns.Add("Id", typeof(string));
              dtTemp.Columns.Add("Name", typeof(string));
            for (int j = 0; j <= _count - 1; j++)
            {
                DataRow dr;
                dr = dtTemp.NewRow();
                dr["Id"] = ListSeCh.Items[j].Value;
                dr["Name"] = ListSeCh.Items[j].Text;
                dtTemp.Rows.Add(dr);
            }
              DataSet ds11 = new DataSet();
              ds11.Merge(dtTemp);

              ds11.WriteXml(Server.MapPath("ss.xml"));

}

Code for the Zip file of "ss.xml"

                     FileStream fs = new FileStream(Server.MapPath("ss.xml"), FileMode.Open,   FileAccess.Read, FileShare.Read);
                    byte[] data = new byte[fs.Length];
                    fs.Read(data, 0, data.Length);
                    FileStream compressed = new FileStream("D:\\New Folder\\WebSite\\zipfolder\\ss.zip", FileMode.OpenOrCreate, FileAccess.ReadWrite);
                    GZipStream gzip = new GZipStream(compressed, CompressionMode.Compress, false);
                    gzip.Write(data, 0, data.Length); 
                    fs.Close();
                    gzip.Close();
                    compressed.Close();

Code for Csv

//From Dataset
                Response.Clear();
                Response.Buffer = true;
                Response.AddHeader("content-disposition", "attachment;filename=CPCB.csv");
                Response.Charset = "";
                Response.ContentType = "application/text";
                StringBuilder sb = new StringBuilder();
                for (int k = 0; k < dtTemp.Columns.Count; k++)
                {
                    //add separator
                    sb.Append(dtTemp.Columns[k].ColumnName + ',');
                }
                //append new line
                sb.Append("\r\n");
                for (int i = 0; i < dtTemp.Rows.Count; i++)
                {
                    for (int k = 0; k < dtTemp.Columns.Count; k++)
                    {
                        //add separator
                        sb.Append(dtTemp.Rows[i][k].ToString().Replace(",", ";") + ',');
                    }
                    //append new line
                    sb.Append("\r\n");
                }
                Response.Output.Write(sb.ToString());

                Response.Flush();
                Response.End();

OR
using Excel = Microsoft.Office.Interop.Excel;

 public void Excel_FromDataTable(DataTable dt)
    {

        Excel.ApplicationClass excel = new Excel.ApplicationClass();
        Excel.Workbook workbook = excel.Application.Workbooks.Add(true);
        try
        {
            int iCol = 0;
            foreach (DataColumn c in dt.Columns)
            {
                iCol++;
                excel.Cells[1, iCol] = c.ColumnName;
            }

            int iRow = 0;
            foreach (DataRow r in dt.Rows)
            {
                iRow++;
                iCol = 0;
                foreach (DataColumn c in dt.Columns)
                {
                    iCol++;
                    excel.Cells[iRow + 1, iCol] = r[c.ColumnName];
                }
            }
        }
        catch (Exception e)
        {
          Console.WriteLine(e);
        }

        if (System.IO.File.Exists("D:\\MyExcelWorkBook.csv"))
            System.IO.File.Delete("D:\\MyExcelWorkBook.csv");
   

        object missing = System.Reflection.Missing.Value;
        workbook.SaveAs("D:\\MyExcelWorkBook",        
        Excel.XlFileFormat.xlCSV, missing, missing,
        false, false, Excel.XlSaveAsAccessMode.xlExclusive,
        missing, missing, missing, missing, missing);
        workbook.Saved = true;
        workbook.Close(false, missing, missing);
        excel.Quit();
        //excel.Visible = true; 
    }