SQL data is saved to an Excel file

         Public stringExportexcel (DataSet ds,stringsavefilename) {            Try            {                if(ds = =NULL)                     return "the database is empty"; BOOLfilesaved =false; Microsoft.Office.Interop.Excel.Application xlapp=NewMicrosoft.Office.Interop.Excel.Application (); if(xlapp = =NULL)                {                    return "Unable to create Excel object, may not have Excel installed on your machine"; } Microsoft.Office.Interop.Excel.Workbooks Workbooks=Xlapp.workbooks; Microsoft.Office.Interop.Excel.Workbook Workbook=workbooks.                ADD (Microsoft.Office.Interop.Excel.XlWBATemplate.xlWBATWorksheet); Microsoft.Office.Interop.Excel.Worksheet Worksheet= (Microsoft.Office.Interop.Excel.Worksheet) workbook. worksheets[1];//get Sheet1//Write Fields                 for(inti =0; I < DS. tables[0]. Columns.count; i++) {worksheet. cells[1, i +1] = ds. tables[0]. Columns[i].                ColumnName; }                //Write Value                 for(intR =0; R < DS. tables[0]. Rows.Count; r++)                {                     for(inti =0; I < DS. tables[0]. Columns.count; i++) {worksheet. Cells[r+2, i +1] = ds. tables[0].                    Rows[r][i];                } System.Windows.Forms.Application.DoEvents (); } worksheet. Columns.EntireColumn.AutoFit ();//column widths are self-adapting.                 if(Savefilename! ="")                {                    Try{workbook. Saved=true; Workbook.                        SaveCopyAs (Savefilename); Filesaved=true; }                    Catch(Exception ex) {filesaved=false; MessageBox.Show ("An error occurred while exporting the file, the file may be being opened! \ n"+Ex.                    Message); }                }                Else{filesaved=false;                } xlapp.quit (); Gc. Collect ();//forcibly destroyed                if(filesaved && System.IO.File.Exists (savefilename)) System.Diagnostics.Process.Start (Savefilename);//Open Excel                return "successfully saved to Excel"; }            Catch(Exception ex) {returnEx.            ToString (); }        }

SQL data is saved to an Excel file