Create excel file with asp.net

First , Add Reference " Microsoft Excel 10.0 Object Library"

private void CreateExcelWorkbook(DataTable dt)
    {

        string strCurrentDir = Server.MapPath(".") + "\\";

        //RemoveFiles(strCurrentDir); // utility method to clean up old files

        Excel.Application oXL;

        Excel._Workbook oWB;

        Excel._Worksheet oSheet;

        Excel.Range oRng;

        try
        {

            GC.Collect();// clean up any other excel guys hangin' around...

            oXL = new Excel.Application();

            oXL.Visible = false;

            //Get a new workbook.

            oWB = (Excel._Workbook)(oXL.Workbooks.Add(Missing.Value));

            oSheet = (Excel._Worksheet)oWB.ActiveSheet;

         

            // Create Header and sheet...

           

            //for (int j = 0; j < myReader.FieldCount; j++)
            //{

            //    oSheet.Cells[1, j + 1] = myReader.GetName(j).ToString();

            //}

            // build the sheet contents

            for(int i=0;i<dt.Rows.Count;i++)
            {

                for (int k = 0; k < dt.Columns.Count; k++)
                {

                    oSheet.Cells[i+1, k+1] = dt.Rows[i][k].ToString();

                }

            }// end while

            oSheet.Name = "my";
            //Format A1:Z1 as bold, vertical alignment = center.

            oSheet.get_Range("A1", "Z1").Font.Bold = true;

            oSheet.get_Range("A1", "Z1").VerticalAlignment = Excel.XlVAlign.xlVAlignCenter;

            //AutoFit columns A:Z.

            oRng = oSheet.get_Range("A1", "Z1");

            oRng.EntireColumn.AutoFit();

            oXL.Visible = false;

            oXL.UserControl = false;

            string strFile = "report" + System.DateTime.Now.Ticks.ToString() + ".xls";

            oWB.SaveAs(strCurrentDir + strFile, Excel.XlFileFormat.xlWorkbookNormal,

            null, null, false, false, Excel.XlSaveAsAccessMode.xlShared, false, false, null, null, null);

            // Need all following code to clean up and extingush all references!!!

            oWB.Close(null, null, null);

            oXL.Workbooks.Close();

            oXL.Quit();

            System.Runtime.InteropServices.Marshal.ReleaseComObject(oRng);

            System.Runtime.InteropServices.Marshal.ReleaseComObject(oXL);

            System.Runtime.InteropServices.Marshal.ReleaseComObject(oSheet);

            System.Runtime.InteropServices.Marshal.ReleaseComObject(oWB);

            oSheet = null;

            oWB = null;

            oXL = null;

            GC.Collect(); // force final cleanup!

            //string strMachineName = Request.ServerVariables["SERVER_NAME"];

            //errLabel.Text = "<A href=http://" + strMachineName + "/ExcelGen/" + strFile + ">Download Report</a>";
            Response.Write("success!");

        }

        catch (Exception theException)
        {

            String errorMessage;

            errorMessage = "Error: ";

            errorMessage = String.Concat(errorMessage, theException.Message);

            errorMessage = String.Concat(errorMessage, " Line: ");

            errorMessage = String.Concat(errorMessage, theException.Source);

            Response.Write(errorMessage);

        }

    }