Question

我从文件中读取行，每行显示在文本框中。我使用事件但app停止并等待加载所有行。显示所有行后。这是代码： public partial class MainWindow：Window { FileReader reader = new FileReader（）; public MainWindow（） { 的InitializeComponent（）; reader.OnReadLine + =消息; }

    private void Message(object sender, LineEventArgs e)
    {
        Dispatcher.Invoke((Action)(() =>
                    {
                        textBox.Text += e.Content + "\n";
                        textBox.Focus();
                        textBox.SelectionStart = textBox.Text.Length;

                    }));
    }

    private void button_Click(object sender, RoutedEventArgs e)
    {
        TaskFactory taskFactory = new TaskFactory();
        var x = taskFactory.StartNew(() => reader.Read());
        Task.WaitAll(x);
    }
}
class LineEventArgs : EventArgs
{
    public string Content { get; }

    public LineEventArgs(string content)
    {
        Content = content;
    }
}


delegate void OnReadLineHandler(object sender, LineEventArgs e);
class FileReader
{
    public event OnReadLineHandler OnReadLine;

    public void Read()
    {
        var fileStream = new FileStream("text.txt", FileMode.Open, FileAccess.Read);
        using (var streamReader = new StreamReader(fileStream, Encoding.UTF8))
        {
            while (!streamReader.EndOfStream)
            {
                OnRead(streamReader.ReadLine());      
            }
        }
    }

    private void OnRead(string text)
    {
        if (OnReadLine != null)
            OnReadLine(this, new LineEventArgs(text));
    }
}

感谢您的建议

Answer 1

你告诉用户界面要等待读取整个文件，因为你说的是Task.WaitAll(x)含义，你说，“等到这个完成了。”而是使用等待如下。

private async void button_Click(object sender, RoutedEventArgs e)
{
    TaskFactory taskFactory = new TaskFactory();
    var x = taskFactory.StartNew(() => reader.Read());
    await x;
}

注意我也可以通过将private void button_Click(object sender, RoutedEventArgs e)更改为private async void button_Click(object sender, RoutedEventArgs e)

来对方法进行异步处理

尝试一下，看看是否有帮助。

WPF多线程与事件

1 个答案: