使用asp.net将数据从excel文件读取到gridView

Question

good day, im reading data from excel file and showing it to gridview. but errors says "The Microsoft Jet database engine cannot open the file ''. It is already opened exclusively by another user, or you need permission to view its data."

what i have done:

1. give full access write to folder for IUSR, NETWORK_SERVICE, NETWORK, EVERYONE, USERS AND ADMIN

thank you in advance.

String filePath = txtBbSource.Text;
    String sheetName = txtSheetName.Text;

    string constr = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + filePath + ";Extended Properties='Excel 8.0;'";
    OleDbConnection con = new OleDbConnection(constr);
    OleDbDataAdapter sda = new OleDbDataAdapter("Select * from [" + sheetName + "$]", con);
    DataTable dt = new DataTable();
    sda.Fill(dt);
    gridBalances.DataSource = dt;  

Answer 1

private void FillGrid(string FilePath, string Extension)
{

        string conStr = "";
        DataTable dt = new DataTable();

        /*Add below Commented in Webconfig*/
         /*   <add name ="Excel03ConString"
     connectionString="Provider=Microsoft.ACE.OLEDB.12.0;Data Source={0};
                     Extended Properties='Excel 8.0;HDR={1}'"/>
          <!--connectionString="Provider=Microsoft.Jet.OLEDB.4.0;Data Source={0};
                     Extended Properties='Excel 8.0;HDR={1}'"/>-->
<add name ="Excel07ConString"
     connectionString="Provider=Microsoft.ACE.OLEDB.12.0;Data Source={0};
                     Extended Properties='Excel 8.0;HDR={1}'"/>
          * */
        switch (Extension)
        {
            case ".xls": //Excel 97-03
                conStr = ConfigurationManager.ConnectionStrings["Excel03ConString"].ConnectionString;
                break;
            case ".xlsx": //Excel 07
                conStr = ConfigurationManager.ConnectionStrings["Excel07ConString"].ConnectionString;
                break;
        }
        conStr = String.Format(conStr, FilePath, "Yes");
        OleDbConnection connExcel = new OleDbConnection(conStr);
        OleDbCommand cmdExcel = new OleDbCommand();
        OleDbDataAdapter oda = new OleDbDataAdapter();

        cmdExcel.Connection = connExcel;
        try
        {
            int m = 1;
            //Get the name of First Sheet
            connExcel.Open();
            DataTable dtExcelSchema;

            dtExcelSchema = connExcel.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null);
            string SheetName = dtExcelSchema.Rows[0]["TABLE_NAME"].ToString();
            connExcel.Close();

            //Read Data from First Sheet
            connExcel.Open();
            cmdExcel.CommandText = "SELECT * From [" + SheetName + "]";
            //oda.SelectCommand = cmdExcel;
            //oda.Fill(dt);
            // connExcel.Close();
            DataTable myColumns = connExcel.GetOleDbSchemaTable(OleDbSchemaGuid.Columns, new object[] { null, null, SheetName, null });

            foreach (DataRow dtRow in myColumns.Rows)
            {
                if (dtRow["COLUMN_NAME"].ToString() == "Sr No" && dtRow["ORDINAL_POSITION"].ToString() == "1")
                {
                    m++;
                }
                else if (dtRow["COLUMN_NAME"].ToString() == "Task Name" && dtRow["ORDINAL_POSITION"].ToString() == "2")
                {
                    m++;
                }
            }
            /*column count in excel*/
            if (m < 2)
            {
                lblErrMsg.Visible = true;
                lblErrMsg.Text = "Selected file is not in required template format.";
                return;
            }
            oda.SelectCommand = cmdExcel;
            oda.Fill(dt);
            connExcel.Close();
        }
        catch (Exception ex)
        {
            lblErrMsg.Visible = true;
            lblErrMsg.Text = "Selected file is not in required template format.";
            return;
        }

        DataTable dt_grd1 = new DataTable();
        DataRow drnewrow = null;


            //upload_plan = 1;
            foreach (DataRow dtRow in dt.Rows)
            {

                if (dtRow["Sr No"].ToString() == "" && dtRow["Task Name"].ToString() != "")
                {
                            dt_grd1.Columns.Add(new DataColumn("ID", typeof(string)));
                            dt_grd1.Columns.Add(new DataColumn("TASK_NAME", typeof(string)));    
                }

                    try
                    {
                        drnewrow = dt_grd1.NewRow();
                        drnewrow["ID"] = "";
                        drnewrow["TASK_NAME"] = dtRow["Task Name"].ToString();

                        dt_grd1.Rows.Add(drnewrow);

                    }
                    catch (Exception ex)
                    {
                        //lblError.Visible = true;
                        ////lblError.Text = ex.Message;// "Authentication failed. Please try later.";
                        //lblError.Text = DataInteraction.Constants.EXCEPTION;
                    }
                }

            /*Using Linq Find same TASK_NAME present in Excel*/
            if (dt_grd1.Rows.Count >= 1)
            {

                var Taskresult = from c in dt_grd1.AsEnumerable()
                                 group c by new
                                 {

                                     TaskName2 = c.Field<dynamic>("TASK_NAME"),


                                 } into g
                                 where g.Count() > 1
                                 select new
                                 {
                                     g.Key.TaskName2,

                                     //  g.Key.Pin,
                                     Noofrec = g.Count()
                                 };

                if (Taskresult.ToList().Count > 0)
                {
                    lblErrMsg.Visible = true;
                    div_err_log.Visible = false;
                    lblErrMsg.Text = "Task with same Name not allowed.";
                    return;
                }
            }
            grdTaskDataCat1.DataSource = dt_grd1;
            grdTaskDataCat1.DataBind();

            /*End 13th Jan'17*/
            lblErrMsg.Visible = true;
            lblErrMsg.Text = "Please confirm the details uploaded and press save to complete the upload of Bid plan.";
            return;


}