背景
我RichTextBox在我的 WinForms 应用程序中使用了一个基本上就像控制台一样的控件。目前，我的应用程序范围的记录器使用委托发布消息，其中一个侦听器是这个 RTB。记录器同步发送大量短（小于 100 个字符）字符串，表示事件调用、状态消息、操作结果等。
使用 BeginInvoke 将这些短消息发布到 RTB 可提供 UI 响应能力，直到繁重的并行处理开始记录大量消息，然后 UI 开始无序发布项目，或者文本远远落后（数百毫秒）。我知道这一点是因为当处理速度变慢或停止时，控制台会继续写一段时间。
我的临时解决方案是同步调用 UI 并添加一个阻塞的集合缓冲区。基本上从 Logger 中取出许多小项目，并将它们组合在一个 stringbuilder 中，然后汇总发布到 RTB。如果 UI 可以跟上，缓冲区会在项目到来时发布它们，但如果队列变得太高，那么它将聚合它们然后发布到 UI。因此，RTB 是零碎更新的，并且在记录大量内容时看起来很紧张。
问题
如何在其自己的 UI 线程上运行控件，以在频繁但小的附加操作期间RichTextBox保持其他按钮的响应相同？Form从研究来看，我认为我需要运行一个 STA 线程并调用Application.Run()它以将 RTB 放在自己的线程上，但是我发现的示例缺乏实质性的代码示例，并且似乎没有任何教程（也许是因为我想要这样做是不明智的吗？）。此外，我不确定单个控件相对于表单的其余部分在其自己的线程上是否存在任何缺陷。（即。关闭主窗体的任何问题，或者 RTB 的 STA 线程是否会随着窗体关闭而死？任何特殊处理？等）
Button一旦您将 3 s 和 a添加RichTextBox到表单中，这应该会证明该问题。我基本上想要完成的是通过将 RTB 放在自己的线程上来分解 BufferedConsumer。大部分代码都是从我的主应用程序中逐字删除的，所以是的，它很丑陋。
using System;
using System.Collections.Concurrent;
using System.Diagnostics;
using System.Drawing;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace WindowsFormsApplication1
{
public partial class Form1 : Form
{
// Fields
private int m_taskCounter;
private static CancellationTokenSource m_tokenSource;
private bool m_buffered = true;
private static readonly object m_syncObject = new object();
// Properties
public IMessageConsole Application_Console { get; private set; }
public BufferedConsumer<StringBuilder, string> Buffer { get; private set; }
public Form1()
{
InitializeComponent();
m_tokenSource = new CancellationTokenSource();
Application_Console = new RichTextBox_To_IMessageConsole(richTextBox1);
Buffer =
new BufferedConsumer<StringBuilder, string>(
p_name: "Console Buffer",
p_appendBuffer: (sb, s) => sb.Append(s),
p_postBuffer: (sb) => Application_Console.Append(sb));
button1.Text = "Start Producer";
button2.Text = "Stop All";
button3.Text = "Toggle Buffering";
button1.Click += (o, e) => StartProducerTask();
button2.Click += (o, e) => CancelAllProducers();
button3.Click += (o, e) => ToggleBufferedConsumer();
}
public void StartProducerTask()
{
var Token = m_tokenSource.Token;
Task
.Factory.StartNew(() =>
{
var ThreadID = Interlocked.Increment(ref m_taskCounter);
StringBuilder sb = new StringBuilder();
var Count = 0;
while (!Token.IsCancellationRequested)
{
Count++;
sb.Clear();
sb
.Append("ThreadID = ")
.Append(ThreadID.ToString("000"))
.Append(", Count = ")
.AppendLine(Count.ToString());
if (m_buffered)
Buffer
.AppendCollection(sb.ToString()); // ToString mimicks real world Logger passing strings and not stringbuilders
else
Application_Console.Append(sb);
Sleep.For(1000);
}
}, Token);
}
public static void CancelAllProducers()
{
lock (m_syncObject)
{
m_tokenSource.Cancel();
m_tokenSource = new CancellationTokenSource();
}
}
public void ToggleBufferedConsumer()
{
m_buffered = !m_buffered;
}
}
public interface IMessageConsole
{
// Methods
void Append(StringBuilder p_message);
}
// http://stackoverflow.com/a/5706085/1718702
public class RichTextBox_To_IMessageConsole : IMessageConsole
{
// Constants
private const int WM_USER = 0x400;
private const int WM_SETREDRAW = 0x000B;
private const int EM_GETEVENTMASK = WM_USER + 59;
private const int EM_SETEVENTMASK = WM_USER + 69;
private const int EM_GETSCROLLPOS = WM_USER + 221;
private const int EM_SETSCROLLPOS = WM_USER + 222;
//Imports
[DllImport("user32.dll")]
private static extern IntPtr SendMessage(IntPtr hWnd, Int32 wMsg, Int32 wParam, ref Point lParam);
[DllImport("user32.dll")]
private static extern IntPtr SendMessage(IntPtr hWnd, Int32 wMsg, Int32 wParam, IntPtr lParam);
// Fields
private RichTextBox m_richTextBox;
private bool m_attachToBottom;
private Point m_scrollPoint;
private bool m_painting;
private IntPtr m_eventMask;
private int m_suspendIndex = 0;
private int m_suspendLength = 0;
public RichTextBox_To_IMessageConsole(RichTextBox p_richTextBox)
{
m_richTextBox = p_richTextBox;
var h = m_richTextBox.Handle;
m_painting = true;
m_richTextBox.DoubleClick += RichTextBox_DoubleClick;
m_richTextBox.MouseWheel += RichTextBox_MouseWheel;
}
// Methods
public void SuspendPainting()
{
if (m_painting)
{
m_suspendIndex = m_richTextBox.SelectionStart;
m_suspendLength = m_richTextBox.SelectionLength;
SendMessage(m_richTextBox.Handle, EM_GETSCROLLPOS, 0, ref m_scrollPoint);
SendMessage(m_richTextBox.Handle, WM_SETREDRAW, 0, IntPtr.Zero);
m_eventMask = SendMessage(m_richTextBox.Handle, EM_GETEVENTMASK, 0, IntPtr.Zero);
m_painting = false;
}
}
public void ResumePainting()
{
if (!m_painting)
{
m_richTextBox.Select(m_suspendIndex, m_suspendLength);
SendMessage(m_richTextBox.Handle, EM_SETSCROLLPOS, 0, ref m_scrollPoint);
SendMessage(m_richTextBox.Handle, EM_SETEVENTMASK, 0, m_eventMask);
SendMessage(m_richTextBox.Handle, WM_SETREDRAW, 1, IntPtr.Zero);
m_painting = true;
m_richTextBox.Invalidate();
}
}
public void Append(StringBuilder p_message)
{
var WatchDogTimer = Stopwatch.StartNew();
var MinimumRefreshRate = 2000;
m_richTextBox
.Invoke((Action)delegate
{
// Last resort cleanup
if (WatchDogTimer.ElapsedMilliseconds > MinimumRefreshRate)
{
// m_richTextBox.Clear(); // Real-world behaviour
// Sample App behaviour
Form1.CancelAllProducers();
}
// Stop Drawing to prevent flickering during append and
// allow Double-Click events to register properly
this.SuspendPainting();
m_richTextBox.SelectionStart = m_richTextBox.TextLength;
m_richTextBox.SelectedText = p_message.ToString();
// Cap out Max Lines and cut back down to improve responsiveness
if (m_richTextBox.Lines.Length > 4000)
{
var NewSet = new string[1000];
Array.Copy(m_richTextBox.Lines, 1000, NewSet, 0, 1000);
m_richTextBox.Lines = NewSet;
m_richTextBox.SelectionStart = m_richTextBox.TextLength;
m_richTextBox.SelectedText = "\r\n";
}
this.ResumePainting();
// AutoScroll down to display newest text
if (m_attachToBottom)
{
m_richTextBox.SelectionStart = m_richTextBox.Text.Length;
m_richTextBox.ScrollToCaret();
}
});
}
// Event Handler
void RichTextBox_DoubleClick(object sender, EventArgs e)
{
// Toggle
m_attachToBottom = !m_attachToBottom;
// Scroll to Bottom
if (m_attachToBottom)
{
m_richTextBox.SelectionStart = m_richTextBox.Text.Length;
m_richTextBox.ScrollToCaret();
}
}
void RichTextBox_MouseWheel(object sender, MouseEventArgs e)
{
m_attachToBottom = false;
}
}
public class BufferedConsumer<TBuffer, TItem> : IDisposable
where TBuffer : new()
{
// Fields
private bool m_disposed = false;
private Task m_consumer;
private string m_name;
private CancellationTokenSource m_tokenSource;
private AutoResetEvent m_flushSignal;
private BlockingCollection<TItem> m_queue;
// Constructor
public BufferedConsumer(string p_name, Action<TBuffer, TItem> p_appendBuffer, Action<TBuffer> p_postBuffer)
{
m_name = p_name;
m_queue = new BlockingCollection<TItem>();
m_tokenSource = new CancellationTokenSource();
var m_token = m_tokenSource.Token;
m_flushSignal = new AutoResetEvent(false);
m_token
.Register(() => { m_flushSignal.Set(); });
// Begin Consumer Task
m_consumer = Task.Factory.StartNew(() =>
{
//Handler
// .LogExceptions(ErrorResponse.SupressRethrow, () =>
// {
// Continuously consumes entries added to the collection, blocking-wait if empty until cancelled
while (!m_token.IsCancellationRequested)
{
// Block
m_flushSignal.WaitOne();
if (m_token.IsCancellationRequested && m_queue.Count == 0)
break;
// Consume all queued items
TBuffer PostBuffer = new TBuffer();
Console.WriteLine("Queue Count = " + m_queue.Count + ", Buffering...");
for (int i = 0; i < m_queue.Count; i++)
{
TItem Item;
m_queue.TryTake(out Item);
p_appendBuffer(PostBuffer, Item);
}
// Post Buffered Items
p_postBuffer(PostBuffer);
// Signal another Buffer loop if more items were Queued during post sequence
var QueueSize = m_queue.Count;
if (QueueSize > 0)
{
Console.WriteLine("Queue Count = " + QueueSize + ", Sleeping...");
m_flushSignal.Set();
if (QueueSize > 10 && QueueSize < 100)
Sleep.For(1000, m_token); //Allow Queue to build, reducing posting overhead if requests are very frequent
}
}
//});
}, m_token, TaskCreationOptions.LongRunning, TaskScheduler.Default);
}
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
protected virtual void Dispose(bool p_disposing)
{
if (!m_disposed)
{
m_disposed = true;
if (p_disposing)
{
// Release of Managed Resources
m_tokenSource.Cancel();
m_flushSignal.Set();
m_consumer.Wait();
}
// Release of Unmanaged Resources
}
}
// Methods
public void AppendCollection(TItem p_item)
{
m_queue.Add(p_item);
m_flushSignal.Set();
}
}
public static partial class Sleep
{
public static bool For(int p_milliseconds, CancellationToken p_cancelToken = default(CancellationToken))
{
//p_milliseconds
// .MustBeEqualOrAbove(0, "p_milliseconds");
// Exit immediate if cancelled
if (p_cancelToken != default(CancellationToken))
if (p_cancelToken.IsCancellationRequested)
return true;
var SleepTimer =
new AutoResetEvent(false);
// Cancellation Callback Action
if (p_cancelToken != default(CancellationToken))
p_cancelToken
.Register(() => SleepTimer.Set());
// Block on SleepTimer
var Canceled = SleepTimer.WaitOne(p_milliseconds);
return Canceled;
}
}
}
