Save and close excel file using C#.

Question

I am not sure why I get the following error for the below code.  Everything seems to work otherwise.
Error found: System.Runtime.InteropServices.COMException (0x8002000B): Invalid index. (Exception from HRESULT: 0x8002000
B (DISP_E_BADINDEX))
Application _application;public void CloseFile(string filename, bool isSaveChanges)
_application.Workbooks[filename].Close(SaveChanges: isSaveChanges);

Answer 1

I' work with excel files with connection you can save data and  close connection Easy.
 //connection String for xls file format.
                    if (fileExtension == ".xls")
                        excelConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + fileLocation + ";Extended Properties=\"Excel 8.0;HDR=Yes;IMEX=2\"";
                    //connection String for xlsx file format.
                    else if (fileExtension == ".xlsx")
                        excelConnectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + fileLocation + ";Extended Properties=\"Excel 12.0;HDR=Yes;IMEX=2\"";
                    //Create Connection to Excel work book and add oledb namespace
                    OleDbConnection excelConnection = new OleDbConnection(excelConnectionString);
                    excelConnection.Open();
DataTable dt = new DataTable();
                    dt = excelConnection.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null);
                    if (dt == null)
                        return null;
                    String[] excelSheets = new String[dt.Rows.Count];
                    int t = 0;
                    //excel data saves in temp file here.
                    foreach (DataRow row in dt.Rows)
                        excelSheets[t] = row["TABLE_NAME"].ToString();
                        t++;
                    OleDbConnection excelConnection1 = new OleDbConnection(excelConnectionString);
                    string query = string.Format("Select * from [{0}]", excelSheets[0]);
                    using (OleDbDataAdapter dataAdapter = new OleDbDataAdapter(query, excelConnection1))
                        dataAdapter.Fill(ds);
Best Regards
Hakim.