C＃多BackgroundWorkers [英] C# Multiple BackgroundWorkers
问题描述
我想设置多个的BackgroundWorker s到做工作，不忙的时候开始做下一个工作位。我似乎无法让他们正常工作。我有下面的代码。
当我设置 FilesToProcess 等于或小于 MaxThreads 它完美但如果我让越高，应用程序冻结。
我相信这是简单的东西，但我无法看到它。
感谢您的任何帮助：）
周杰伦
使用系统;
使用System.ComponentModel;
使用的System.Threading;使用System.Windows.Forms的
;
命名空间bgwtest
{
公共部分Form1类：表格
{
私人const int的MaxThreads = 20;
私人const int的FilesToProcess = 21;
私人BackgroundWorker的[] threadArray =新的BackgroundWorker [MaxThreads]
公共Form1中（）
{
的InitializeComponent（）;
}
私人无效Form1Load（对象发件人，EventArgs五）
{
InitializeBackgoundWorkers（）;
}
私人无效InitializeBackgoundWorkers（）
{
为（VAR F = 0; F< MaxThreads;˚F++）
{
threadArray [F] =新的BackgroundWorker（）;
threadArray [F] .DoWork + =新DoWorkEventHandler（BackgroundWorkerFilesDoWork）;
threadArray [F] .RunWorkerCompleted + =新RunWorkerCompletedEventHandler（BackgroundWorkerFilesRunWorkerCompleted）;
threadArray [F] .WorkerReportsProgress = TRUE;
threadArray [F] .WorkerSupportsCancellation = TRUE;
}
}
私人无效的button1_Click（对象发件人，EventArgs五）
{
为（VAR F = 0; F< FilesToProcess;˚F++ ）
{
VAR fileProcessed = FALSE;
，而（fileProcessed！）
{
为（VAR threadNum = 0; threadNum< MaxThreads; threadNum ++）！
{
如果（threadArray [threadNum] .IsBusy ）
{
Console.WriteLine（启动主题：{0}，threadNum）;
threadArray [threadNum] .RunWorkerAsync（F）;
fileProcessed = TRUE;
中断;
}
}
如果（fileProcessed！）
{
Thread.sleep代码（50）;
}
}
}
}
私人无效BackgroundWorkerFilesDoWork（对象发件人，DoWorkEventArgs E）
{
ProcessFile（（ INT）e.Argument）;
e.Result =（INT）e.Argument;
}
私有静态无效ProcessFile（INT文件）
{
Console.WriteLine（处理文件：{0}，文件）;
}
私人无效BackgroundWorkerFilesRunWorkerCompleted（对象发件人，RunWorkerCompletedEventArgs E）
{
如果（e.Error！= NULL）
{
MessageBox.Show（e.Error.Message）;
}
Console.WriteLine（已处理文件：{0}（INT）e.Result）;
}
}
}
这个问题似乎是，你的工人永远不会完成。这是为什么，我不知道;它是与事实，你是从运行它们的方法（和线程）自身没有完成。我能够通过创建另一个工人将文件分配给工人阵列来解决这个问题：
私人BackgroundWorker的assignmentWorker;
私人无效InitializeBackgoundWorkers（）{
assignmentWorker =新的BackgroundWorker（）;
assignmentWorker.DoWork + = AssignmentWorkerOnDoWork;
// ...
}
私人无效AssignmentWorkerOnDoWork（对象发件人，DoWorkEventArgs doWorkEventArgs）{
为（VAR F = 0; F< FilesToProcess;˚F++ ）{
VAR fileProcessed = FALSE;
，而（fileProcessed！）{
为（VAR threadNum = 0; threadNum< MaxThreads; threadNum ++）{
如果{
控制台（threadArray [threadNum] .IsBusy！）。的WriteLine（启动主题：{0}，threadNum）;
threadArray [threadNum] .RunWorkerAsync（F）;
fileProcessed = TRUE;
中断;
}
}
如果{
Thread.sleep代码（50）（fileProcessed！）;
中断;
}
}
}
}
私人无效的button1_Click（对象发件人，EventArgs五）{
assignmentWorker.RunWorkerAsync（）;
}
我不是很满意这个答案，因为我不知道为什么，确切地说，它不工作，你最初的设计吧。也许别人可以回答这个问题......？ 。至少这将让你一个工作版本
编辑：您原来的版本没有工作，因为 BackgroundWorkerFilesRunWorkerCompleted 同一个线程的button1_Click （UI线程）上运行。既然你不释放在UI线程，线程永远不会标示为完成。
I am trying to setup multiple BackgroundWorkers to do work and when not busy start doing the next bit of work. I can't seem to get them working properly. I have the below code.
When I set FilesToProcess equal or less than MaxThreads it works perfectly although if I make it higher, the app freezes.
I am sure it is something simple, but I just can't see it.
Thanks for any help :)
Jay
using System;
using System.ComponentModel;
using System.Threading;
using System.Windows.Forms;
namespace bgwtest
{
public partial class Form1 : Form
{
private const int MaxThreads = 20;
private const int FilesToProcess = 21;
private BackgroundWorker[] threadArray = new BackgroundWorker[MaxThreads];
public Form1()
{
InitializeComponent();
}
private void Form1Load(object sender, EventArgs e)
{
InitializeBackgoundWorkers();
}
private void InitializeBackgoundWorkers()
{
for (var f = 0; f < MaxThreads; f++)
{
threadArray[f] = new BackgroundWorker();
threadArray[f].DoWork += new DoWorkEventHandler(BackgroundWorkerFilesDoWork);
threadArray[f].RunWorkerCompleted += new RunWorkerCompletedEventHandler(BackgroundWorkerFilesRunWorkerCompleted);
threadArray[f].WorkerReportsProgress = true;
threadArray[f].WorkerSupportsCancellation = true;
}
}
private void button1_Click(object sender, EventArgs e)
{
for (var f = 0; f < FilesToProcess; f++)
{
var fileProcessed = false;
while (!fileProcessed)
{
for (var threadNum = 0; threadNum < MaxThreads; threadNum++)
{
if (!threadArray[threadNum].IsBusy)
{
Console.WriteLine("Starting Thread: {0}", threadNum);
threadArray[threadNum].RunWorkerAsync(f);
fileProcessed = true;
break;
}
}
if (!fileProcessed)
{
Thread.Sleep(50);
}
}
}
}
private void BackgroundWorkerFilesDoWork(object sender, DoWorkEventArgs e)
{
ProcessFile((int)e.Argument);
e.Result = (int)e.Argument;
}
private static void ProcessFile(int file)
{
Console.WriteLine("Processing File: {0}", file);
}
private void BackgroundWorkerFilesRunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
if (e.Error != null)
{
MessageBox.Show(e.Error.Message);
}
Console.WriteLine("Processed File: {0}", (int)e.Result);
}
}
}
The problem appears to be that your workers are never completing. Why this is, I'm not sure; it has something to do with the fact that the method (and thread) you are running them from is not itself completing. I was able to solve the problem by creating another worker to assign files to the worker array:
private BackgroundWorker assignmentWorker;
private void InitializeBackgoundWorkers() {
assignmentWorker = new BackgroundWorker();
assignmentWorker.DoWork += AssignmentWorkerOnDoWork;
// ...
}
private void AssignmentWorkerOnDoWork( object sender, DoWorkEventArgs doWorkEventArgs ) {
for( var f = 0; f < FilesToProcess; f++ ) {
var fileProcessed = false;
while( !fileProcessed ) {
for( var threadNum = 0; threadNum < MaxThreads; threadNum++ ) {
if( !threadArray[threadNum].IsBusy ) {
Console.WriteLine( "Starting Thread: {0}", threadNum );
threadArray[threadNum].RunWorkerAsync( f );
fileProcessed = true;
break;
}
}
if( !fileProcessed ) {
Thread.Sleep( 50 );
break;
}
}
}
}
private void button1_Click( object sender, EventArgs e ) {
assignmentWorker.RunWorkerAsync();
}
I'm not happy with this answer because I don't know why, exactly, it didn't work as you originally designed it. Perhaps someone else can answer that...? At least this will get you a working version.
EDIT: Your original version didn't work because the BackgroundWorkerFilesRunWorkerCompleted runs on the same thread as button1_Click (the UI thread). Since you are not freeing up the UI thread, the thread is never getting marked as complete.
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