WPF 精修篇 长时间线程加取消功能

原文:WPF 精修篇 长时间线程加取消功能

1. <Grid>
2. <Grid.RowDefinitions>
3. <RowDefinition Height="11*"/>
4. <RowDefinition Height="29*"/>
5. </Grid.RowDefinitions>
6. <StackPanel Orientation="Horizontal" Margin="0" VerticalAlignment="Center">
7. <Label>开始数据</Label>
8. <TextBox x:Name="beginText" HorizontalAlignment="Left" Height="31" TextWrapping="Wrap" Text="100" VerticalAlignment="Top" Width="100"/>
9. <Label>结束数据</Label>
10. <TextBox x:Name="endText" HorizontalAlignment="Left" Height="31" TextWrapping="Wrap" Text="1000000000" VerticalAlignment="Top" Width="100"/>
11. <Button x:Name="button" Content="开始" HorizontalAlignment="Center" VerticalAlignment="Center" Width="75" Click="Button_Click"/>
12. <Button x:Name="Cancel" Content="取消" HorizontalAlignment="Center" VerticalAlignment="Center" Width="75" Click="Cancel_Click"/>
13. </StackPanel>
14. <StackPanel Margin="0" Grid.Row="1">
15. <TextBlock x:Name="odd" TextWrapping="Wrap" Text="奇数数量："/>
16. <TextBlock x:Name="even" TextWrapping="Wrap" Text="偶数数量："/>
17. </StackPanel>
18. </Grid>

1. private int oddcount =0;
2. private int evencount =0;
3. public void Make(int from ,int to)
4. {
5. for (int i = from; i < to; i++)
6. {
7. if (TokenSource.IsCancellationRequested)
8. {
9. evencount = -1;
10. oddcount = -1;
11. return;
12. }
13. if (i % 2 == 0)
14. {
15. evencount++;
16. }
17. else
18. {
19. oddcount++;
20. }
21. }
22. }
23. private void Button_Click(object sender, RoutedEventArgs e)
24. {
25. int from=0;
26. int to = 0;
27. if(int.TryParse(beginText.Text,out from)&&int.TryParse(endText.Text,out to) )
28. {
29. button.IsEnabled = false;
30. ThreadPool.QueueUserWorkItem(_ =>
31. {
32. TokenSource = new CancellationTokenSource();
33. Make(from, to);
35. Dispatcher.BeginInvoke(new Action(() =>
36. {
37. if (oddcount < 0 || evencount < 0)
38. {
39. odd.Text = "操作取消";
40. even.Text = "操作取消";
41. }
42. else
43. {
44. odd.Text = "奇数数量：" + oddcount;
45. even.Text = "偶数数量：" + evencount;
46. }
47. button.IsEnabled = true;
48. }));
50. });
52. }
54. }
56. public CancellationTokenSource TokenSource = null;
57. private void Cancel_Click(object sender, RoutedEventArgs e)
58. {
59. if (TokenSource != null)
60. {
61. TokenSource.Cancel();
62. TokenSource = null;
63. }
65. }