2017-10-04 72 views
0

我在C#中有一个程序,我使用while循环从文件中读取行。我希望能够每隔5秒左右显示行号,而不减慢while循环,这样用户就可以看到它们有多远。任何想法如何做到这一点?C#在while循环中调用函数每X秒没有阻塞循环

CODE

try 
    { 
     // Create an instance of StreamReader to read from a file. 
     // The using statement also closes the StreamReader. 
     Stopwatch sw = Stopwatch.StartNew(); 
     using (StreamReader sr = new StreamReader(@"C:\wamp64\www\brute-force\files\antipublic.txt")) 
     { 
      String line; 
      int lines = 0; 
      // Read and display lines from the file until the end of 
      // the file is reached. 
      using (System.IO.StreamWriter file = new System.IO.StreamWriter("C:/users/morgan/desktop/hash_table.txt")) 
      { 
       while ((line = sr.ReadLine()) != null) 
       { 
        file.WriteLine(CreateMD5(line)+':'+line); 
        lines++; 
       } 
      } 
     } 

     sw.Stop(); 
     Console.WriteLine("Time taken: {0}s", sw.Elapsed.TotalSeconds); 
     Console.ReadLine(); 
    } 
    catch (Exception e) 
    { 
     // Let the user know what went wrong. 
     Console.WriteLine("The file could not be read:"); 
     Console.WriteLine(e.Message); 
    } 
} 
+0

在后台线程中运行文件读取代码并向UI线程发送通知。 –

+1

不能在你的while循环中的'++ ++'之后使用一个简单的'if(sw.Elapsed.TotalSeconds%5 == 0)Console.WriteLine(lines +“行读到目前为止...”);'' –

+1

简单的Console.WriteLine每5秒钟不会显着减慢循环。或者您可以使用Task.Run –

回答

3

可以使用BackgroundWorker类来实现这一目标。只要看MSDN的例子就可以了解如何初学这门课。

您可以为BackgroundWorker的一个“DoWork的”方法与ReportProgress调用是这样的:

private void backgroundWorker_DoWork(object sender, DoWorkEventArgs e) 
{ 
    BackgroundWorker worker = sender as BackgroundWorker; 

    Stopwatch sw = Stopwatch.StartNew(); 
    using (StreamReader sr = new StreamReader(@"path")) 
    { 
     String line; 
     int lines = 0; 

     using (System.IO.StreamWriter file = new System.IO.StreamWriter("path")) 
     { 
      while ((line = sr.ReadLine()) != null) 
      { 
       file.WriteLine(CreateMD5(line)+':'+line); 
       worker.ReportProgress(lines++); 
      } 
     } 
    } 
} 

要显示在ProgressChanged事件你只需我们可以使用Console.WriteLine进度()。

+0

MSDN文档指出ProgressChanged事件处理程序在创建BackgroundWorker的线程上执行。 DoWork应该在与BackgroundWorker的创建实例不同的线程上运行。 – Shamshiel