線程在結束線程循環之前沒有完成任務

Question

因此，我前段時間做了類似的事情，但這本質上是一個（特定）網站的用戶名檢查器，它們可以通過文本文件加載用戶名，它會把它變成一個列表框，現在我有了開始按鈕，它意味着檢查每個用戶名。然而，之前，他們在檢查時凍結了程序，但它工作正常。我試圖讓它「穿線」，所以它不會凍結。

現在的問題是，它不檢查所有，並立即完成。

CODE：

Private Sub Button6_Click(sender As Object, e As EventArgs) Handles Button6.Click 
    Button6.Enabled = False 
    Dim goodUsers As New SaveFileDialog() 
    goodUsers.Filter = "TXT file (*.txt)|*.txt" 
    Dim flag As Boolean 
    Dim Incomplete As Integer = 0 
    Dim Taken As Integer = 0 
    Dim sb As New StringBuilder 
    If goodUsers.ShowDialog() = DialogResult.OK Then 
     Dim checkerMT As New Thread(
      Sub() 
       For Each i As String In UsernameList.Items 
        WebRequest.Create("http://yatobooter.cf/other/checkusr.php?username=" + i.ToString) 

        Dim cResult As String = New System.Net.WebClient().DownloadString("http://yatobooter.cf/other/checkusr.php?username=" + i.ToString).ToString 

        If cResult = "taken" Then 
         flag = False 
        ElseIf cResult = "nottaken" Then 
         flag = True 
        End If 

        If flag = True Then 
         sb.Append(i & vbNewLine) 
        Else 
         Incomplete = Incomplete + 1 
         Taken = UsernameList.Items.Count - Incomplete 
        End If 
       Next 
      End Sub 
     ) 
     checkerMT.Start() 
     Try 
      File.WriteAllText(goodUsers.FileName, sb.ToString) 
     Catch ex As Exception 
      Exit Sub 
     End Try 
    End If 
    MessageBox.Show("Checking available usernames, complete!", "NameSniper Pro") 
    Button6.Enabled = True 
End Sub 

Answer 1

1. 的SaveFileDialog可以用作 「使用指令」

2. 爲什麼你創建一方面的WebRequest ，另一方面使用webclient？這根本沒有意義。

3. 而不是你纔怪條件的，寫：

標誌=（cResult.Equals（ 「nottaken」））

你想要的所有代碼在你的線程中當前運行的動作也必須在你的線程中運行，因爲它是異步的。

你，如果你使用一個線程 等內的用戶控件調用..

請打開選項嚴格上和Option推斷關

有很多其他事情你可以做得更好。 請自行刪除webrequest和webclient組合，這根本沒有意義。從比其他UI線程

Private Sub Button6_Click(sender As Object, e As EventArgs) Handles Button6.Click 

    Dim Incomplete As Integer = 0 
    Dim Taken As Integer = 0 
    Dim sb As New StringBuilder 

    Using goodUsers As SaveFileDialog = new SaveFileDialog() 
    goodUsers.Filter = "TXT file (*.txt)|*.txt" 

    If not goodUsers.ShowDialog() = DialogResult.OK Then Exit Sub 
     Dim checkerMT As New Thread(
      Sub() 

      Me.invoke(sub() 
     Button6.Enabled = False 
       For Each i As String In UsernameList.Items 
        WebRequest.Create("http://yatobooter.cf/other/checkusr.php?username=" + i.ToString) 

        Dim cResult As String = New System.Net.WebClient().DownloadString("http://yatobooter.cf/other/checkusr.php?username=" + i.ToString).ToString 

        If (cResult.toLower().Equals("nottaken")) Then 
         sb.Append(String.Concat(i , Environment.NewLine) 
        Else 
         Incomplete += 1 
         Taken = UsernameList.Items.Count - Incomplete 
        End If 

       Next 
       File.WriteAllText(goodUsers.FileName, sb.ToString) 
       Button6.Enabled = True 
       MessageBox.Show("Checking available usernames, complete!", "NameSniper Pro") 
      End Sub) 
      End Sub 
     ) 
     checkerMT.IsBackground = True; 
     checkerMT.Start() 


End Sub 

Answer 2

您不能訪問UI元素（UsernameList.Items）：

看看這個，我清除了一點點。相反，請在您的表單中添加一個後臺工作人員來處理基本的線程工作（進度報告，完成報告，異常處理）。傳遞給這個包含您的工作需要完成其工作而不與UI交互的設置的對象。

Private Sub Button6_Click(sender As Object, e As EventArgs) Handles Button6.Click 
    Button6.Enabled = False 
    Dim goodUsers As New SaveFileDialog() 
    goodUsers.Filter = "TXT file (*.txt)|*.txt" 

    If goodUsers.ShowDialog() = DialogResult.OK Then 
     'Note: You'll need to add the filenames 
     BackgroundWorker1.RunWorkerAsync(New State() With {.Names = {}, .FileName = goodUsers.FileName}) 
    End If 

End Sub 

Class State 
    Public Names As List(Of String) 
    Public StringBuilder As New System.Text.StringBuilder 
    Public Incomplete As Integer 
    Public Taken As Integer 
    Public FileName As String 
End Class 

Private Sub BackgroundWorker1_DoWork(sender As System.Object, e As System.ComponentModel.DoWorkEventArgs) Handles BackgroundWorker1.DoWork 
    Dim state = CType(e.Argument, State) 
    For Each i As String In state.Names 

     Using cli = New System.Net.WebClient() 

      Dim cResult = cli.DownloadString("http://yatobooter.cf/other/checkusr.php?username=" + i.ToString).ToString 
      If cResult = "nottaken" Then 
       state.StringBuilder.Append(i & vbNewLine) 
      Else 
       state.Incomplete = state.Incomplete + 1 
       state.Taken = state.Names.Count - state.Incomplete 
      End If 

     End Using 
    Next 
    IO.File.WriteAllText(state.FileName, state.StringBuilder.ToString) 
End Sub 

Private Sub BackgroundWorker1_RunWorkerCompleted(sender As Object, e As System.ComponentModel.RunWorkerCompletedEventArgs) Handles BackgroundWorker1.RunWorkerCompleted 
    If e.Error IsNot Nothing Then 
     MessageBox.Show(e.Error.ToString(), "Error") 
    Else 
     MessageBox.Show("Checking available usernames, complete!", "NameSniper Pro") 
    End If 
    Button6.Enabled = True 
End Sub