等待很长时间从数据库中获取数据

Question

在获取数据的同时，似乎很长一段时间，我们无法在这段时间内完成另一项任务。我正在为此使用BAckGroundWOrker。但似乎获取所有数据后等待很长一段时间仅在该应用运行过程中出现细微

private void btnExrtPDF_Click(object sender, RoutedEventArgs e) 
    { 
     btnExrtPDF.IsEnabled = false; 
     Collection.Clear();     

     long NoOfRecords = 10000; 
     long RecordsIcrease = 10000; 
     SaveFileDialog xsfd = new SaveFileDialog() 
     { 
      FileName = "Book1", 
      DefaultExt = ".xlsx", 
      Filter = "Excel Document|*.xlsx", 
      InitialDirectory = new System.IO.DirectoryInfo(Environment.GetFolderPath(Environment.SpecialFolder.Desktop)).ToString() 
     }; 
     Nullable<bool> result = xsfd.ShowDialog(); 
     System.Data.DataTable batchFCSB = new System.Data.DataTable(); 
     int row = 0; 
     if (result == true) 
     { 

      DetailReportFCBuySell = AlyexWCFService.DL.DLTTIn.FCBuySELL(transactionName, isDetails, Convert.ToDateTime(dateEdtStartDate.EditValue).Date, Convert.ToDateTime(dtpEditEndDate.EditValue).Date, Customerid, ProductID, branchID, NoOfRecords, PageIndex - 1, isBuy); 
      batchFCSB = DetailReportFCBuySell.ToDataTable(); 
      Collection.Add(row, batchFCSB); 
      row = 1; 
      PageIndex++; 

      for (long k = NoOfRecords; k < DetailReportFCBuySell.FirstOrDefault().TotalRecords; k = +NoOfRecords) 
      { 

        new AlxServiceClient().Using(channel => 
        { 
         DetailReportFCBuySell = new ObservableCollection<DLReports.FCBuySellDetail>(); 
         DetailReportFCBuySell = AlyexWCFService.DL.DLTTIn.FCBuySELL(transactionName, isDetails, Convert.ToDateTime(dateEdtStartDate.EditValue).Date, Convert.ToDateTime(dtpEditEndDate.EditValue).Date, Customerid, ProductID, branchID, NoOfRecords, PageIndex - 1, isBuy); 
         batchFCSB = new System.Data.DataTable(); 
         batchFCSB = DetailReportFCBuySell.ToDataTable(); 
         Collection.Add(row, batchFCSB); 
         row++; 

       }); 
       NoOfRecords = NoOfRecords + RecordsIcrease; 
      } 


      for (int k = 0; k < Collection.Keys.Count; k++) 
      { 
       string xlsxFile = string.Empty; 
       xlsxFile = System.IO.Path.GetTempFileName();      

       TableView temp = new TableView(); 
       temp.DataContext = (Collection.Where(i => i.Key == k).FirstOrDefault().Value); 
       // ExportToXlsx(temp, xlsxFile); 
      } 
      } 
m_oWorker.RunWorkerAsync(); 
} 

Answer 1

我做的EditValue到一个单独的对象，并调用该对象的线程

DateTime startDate = Convert.ToDateTime(dateEdtStartDate.EditValue).Date; 
DateTime endDate = Convert.ToDateTime(dtpEditEndDate.EditValue).Date; 

private DetailReportFCBuySell FetchRecord() 
{ 
return ObservableCollection<DLReports.FCBuySellDetail> temp = AlyexWCFService.DL.DLTTIn.FCBuySELL(transactionName, isDetails, startDate, endDate, Customerid, ProductID, branchID, NoOfRecords, PageIndex - 1, isBuy); 
} 

Answer 2

代码块恍如从Click事件的开始运行，而不必调用BGWorker，考虑到代码块移动到一个单一的像

private DetailReportFCBuySell FetchRecord() 
{ 
    return AlyexWCFService.DL.DLTTIn.FCBuySELL(transactionName, isDetails, Convert.ToDateTime(dateEdtStartDate.EditValue).Date, Convert.ToDateTime(dtpEditEndDate.EditValue).Date, Customerid, ProductID, branchID, NoOfRecords, PageIndex - 1, isBuy); 
} 

功能，并呼吁在m_oWorker做工作时此功能

private void bw_DoWork(object sender, DoWorkEventArgs e) 
{ 
    FetchRecord(); 
} 

阅读更多关于https://msdn.microsoft.com/en-us/library/cc221403(v=vs.95).aspx#code-snippet-3