How to import excel sheet rows values into SQL table database

private void button2_Click(object sender, EventArgs e)
        {
            ////user excel
            DataSet tbds = new DataSet();
            if (openFileDialog1.ShowDialog() == DialogResult.OK)
            {
                string FileName = Path.GetFileName(openFileDialog1.FileName);
                HFExcel.Text = FileName.Trim();
                string Extension = Path.GetExtension(openFileDialog1.FileName);
                string FilePath = System.Windows.Forms.Application.StartupPath + "\\App_Data\\" + FileName;
                System.IO.File.Copy(openFileDialog1.FileName, FilePath);
                string conStr = string.Empty;
                switch (Extension)
                {
                    case ".xls": //Excel 97-03
                        conStr = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + FilePath + ";Extended Properties=\"Excel 8.0;HDR=Yes;IMEX=2\"";
                        break;
                    case ".xlsx": //Excel 07
                        conStr = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + FilePath + ";Extended Properties=\"Excel 12.0;HDR=Yes;IMEX=2\"";
                        break;
                }
                OleDbConnection connExcel = new OleDbConnection(conStr);
                OleDbDataAdapter oda = new OleDbDataAdapter();
                DataTable dt = new DataTable();

                try
                {
                    connExcel.Open();
                    DataTable dtExcelSchema;
                    dtExcelSchema = connExcel.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null);

                    var SheetName = dtExcelSchema.Rows[0]["TABLE_NAME"].ToString();
                    connExcel.Close();
                    //Read Data from First Sheet.
                    connExcel.Open();
                    OleDbCommand cmdExcel = new OleDbCommand("SELECT * From [" + SheetName + "]", connExcel);
                    cmdExcel.CommandText = "SELECT * From [" + SheetName + "]";
                    oda.SelectCommand = cmdExcel;
                    oda.Fill(tbds);

                    DataTable exceldt = tbds.Tables[0];
                    string Result = string.Empty;
                    int TotalCount = 0;
                    int ResultCount = 0;
                    int FailedCount = 0;
                    int AlreadyCount = 0;

                    List<string> ListLinkedIds = new List<string>();
                    // Convert empty cells in of DataTable to NULL for VARCHAR column and 0 for other.
                    for (int i = 0; i < exceldt.Rows.Count; i++)
                    {
                        for (int j = 0; j < exceldt.Columns.Count; j++)
                        {
                            if (String.IsNullOrEmpty(exceldt.Rows[i][j].ToString()))
                            {
                                if (exceldt.Columns[j].DataType == typeof(string))
                                {
                                    exceldt.Rows[i][j] = "NULL";
                                }
                                else
                                {
                                    exceldt.Rows[i][j] = 0;
                                }
                            }
                        }
                    }
                    if (exceldt.Rows.Count > 0)
                    {
                         MessageBox.Show("Enter");
                        for (int i = 0; i < exceldt.Rows.Count; i++)
                        {
                            MessageBox.Show("Enter again");
                            objBO.QueryType = "Insert";
           objBO.EmpId = exceldt.Rows[i]["EmployeeId"].ToString().Trim();
           objBO.LocationId = exceldt.Rows[i]["Location"].ToString().Trim();
           objBO.FirstName = exceldt.Rows[i]["FirstName"].ToString().Trim();
           objBO.LastName = exceldt.Rows[i]["LastName"].ToString().Trim();
      objBO.Gender = exceldt.Rows[i]["Gender"].ToString().Trim();
       
     objBO.City = exceldt.Rows[i]["City"].ToString().Trim();
     objBO.Address = exceldt.Rows[i]["Address"].ToString().Trim();
 objBO.DOB = ValidateClass.ConvDMYTOYMD(exceldt.Rows[i}["DOB"].ToString()).Trim();
                            
         objBO.State = exceldt.Rows[i]["State"].ToString().Trim();
         objBO.MobileNo = exceldt.Rows[i]["PhoneNo"].ToString().Trim();
           objBO.EmailId = exceldt.Rows[i]["Email"].ToString().Trim();
  objBO.UserName = exceldt.Rows[i]["UserName"].ToString().Trim();
 objBO.UserRole = exceldt.Rows[i]["Role"].ToString().Trim();
 objBO.Password = PasswordCode.Encryptdata(exceldt.Rows[i]["Password"].ToString()).Trim();
 objBO.LoginPin = exceldt.Rows[i]["LoginPin"].ToString().Trim();
   
   objBO.CreatedBy = userName;
    objBO.TransactionFlag = "N";
   //Result = objBAL.ProductMaster(objBO);
                            Result = objBAL.UsersMaster(objBO);
                            if (Result == "Success")
                            {
                                ResultCount = ResultCount + 1;
                            }
                            else if (Result == "Already")
                            {
                                AlreadyCount = AlreadyCount + 1;
                            }
                            else
                            {
                                FailedCount = FailedCount + 1;
                            }
                            
                          



                        }
                       

                    }

                }
                catch (Exception ex)
                {
                    MessageBox.Show(ex.Message);

                    
                }
                finally
                {
                    MessageBox.Show("Imported Successfully!");
                    connExcel.Close();
                    
                    FileInfo file = new FileInfo(FilePath);
                    /*if (file.Exists)
                        file.Delete();*/
                    //MessageBox.Show("finally");
                    if (System.IO.File.Exists(FilePath))
                    {
                        System.IO.File.Delete(FilePath);
                    }
                    //MessageBox.Show("deleted");
                }
            }
            else
            {
                MessageBox.Show("no rows");
            }
        }
    }
}