一流的設計 - 如何管理多個線程響應

Question

我需要關於如何最好地設計一組類用於管理多線程C＃應用程序，我發展一些幫助。 我已經成功創建了一個ThreadContainer類來啓動一系列線程。 主題從特定網站下載財務數據。 對於每個通過的網站，他們將打開相同的基本網址，但使用不同的符號。 因此，＃結果等於每個網站傳遞的符號數量。 然後，根據該請求的線程結果以不同的方式處理的網站上... 這裏是簡化ThreadContainer代碼：

public class ThreadContainer 
{ 
private int ConcurrentThreads; 
private string Website; 
public string URL; 
private Queue SymQueue; 

//Constructor 
public ThreadContainer(string website, Queue symQueue) 
{ 
    Website = website; 
    SymQueue = symQueue; 
} 

//Start 
public void start(int concurrent) 
{ 
    ConcurrentThreads = concurrent; 

    //Start the Concurrent Threads 
    for (int ThreadNum = 1; ThreadNum <= ConcurrentThreads; ThreadNum++) 
    { 
     //Get a symbol from the queue 
     Sym = SymQueue.Dequeue().ToString(); 

     //Build the URL 
     URL = string.Format(Constants.URL(Website), Sym); 

     //Create a new Asynch thread 
     AsynchThread j = new AsynchThread(ThreadNum); 

     //Start the AsyncThread class with the BackgoundWorker 
     j.Start(Sym, URL); 
    } 
} 

//Method called when the Backgroundworker thread has terminated 
private void AsynchThread1_JobCompleted(object sender, EventArgs e) 
{ 
    // Get the AsynchThread object 
    AsynchThread j = (AsynchThread)sender; 

     //Get the symbol name 
     String Sym = j.Sym; 

     //Get the result with the Webpage content 
     RunWorkerCompletedEventArgs re = e as RunWorkerCompletedEventArgs; 
     String result = re.Result.ToString(); 

     /* HERE EACH THREAD RETURNS THE WEBSITE CONTENT. 
     * DEPENDING ON THE WEBSITE THAT WAS REQUESTED SEVERAL ACTIONS MAY BE EXECUTED. 
     */ 
     switch(website) 
     { 
      case "WebsiteA": 
       // With WebsiteA I would like to : 
       // 1. extract the symbol data 
       // 2. return the result for this symbol to the calling class. 

      case "WebsiteB": 
       // With WebsiteB I would like to: 
       // 1. extract the symbol data (Webpage design is different from WebsiteA) 
       // 2. store each symbol data in a database table 

      case "WebsiteC": 
       // With WebsiteB I would like to: 
       // 1. extract the symbol data (Webpage design is different from WebsiteA and WebsiteB) 
       // 2. put the results in a queue 

      case ... 

      default:    
       return ""; 
     }   

     // Reuse the thread that has just completed 
     //If there are items left in the queue... 
     if (SymQueue.Count > 0) 
      //...get the new Sym value... 
      NewSym = SymQueue.Dequeue().ToString(); 

     //If NewSym is valid ... 
     if (!String.IsNullOrEmpty(NewSym)) 
     { 
      //...build the URL... 
      String NewURL = string.Format(Constants.URL(Website), NewSym); 

      //...then restart the thread with the new parameters 
      j.Start(NewSym, NewURL); 
     }  
    } 
} 

我想知道什麼是設計的最好方式AsynchThread1_JobCompleted 方法。 當每個線程終止，應執行以下任務，這種方法被稱爲：

1. 得到的網頁內容
2. 從網頁中提取數據
3. 將數據發送給調用者或保存數據到數據庫或將數據插入到隊列中。
4. 檢查隊列是否仍有項目，並使用新的URL重新啓動線程，以便打開新的網頁。

我該如何設計方法，以便每次需要添加新網站時都不必修改代碼？ 另外，我應該使用相同的AsynchThread，下載頁面提取數據，保存到數據庫等...或者更好的另一個線程呢？ 我想有以下一種單一職責原則的ThreadContainer類...

感謝