1
我已经尝试了很多方法,下面是当前的迭代。我想我刚刚实施了这一切都是错误的。我试图完成的是以这样的方式处理这个异步结果,直到它返回并且我完成了我的添加缩略图调用,我将不会再请求调用imageProvider.BeginGetImage。使用Mutex在C#中执行异步操作的问题
要澄清,我的问题是双重的。为什么我所做的事似乎从未停止过我的Mutex.WaitOne()调用,以及处理这种情况的正确方法是什么?
/// <summary>
/// re-creates a list of thumbnails from a list of TreeElementViewModels (directories)
/// </summary>
/// <param name="list">the list of TreeElementViewModels to process</param>
public void BeginLayout(List<AiTreeElementViewModel> list)
{
// *removed code for canceling and cleanup from previous calls*
// Starts the processing of all folders in parallel.
Task.Factory.StartNew(() =>
{
thumbnailRequests = Parallel.ForEach<AiTreeElementViewModel>(list, options, ProcessFolder);
});
}
/// <summary>
/// Processes a folder for all of it's image paths and loads them from disk.
/// </summary>
/// <param name="element">the tree element to process</param>
private void ProcessFolder(AiTreeElementViewModel element)
{
try
{
var images = ImageCrawler.GetImagePaths(element.Path);
AsyncCallback callback = AddThumbnail;
foreach (var image in images)
{
Console.WriteLine("Attempting Enter");
synchMutex.WaitOne();
Console.WriteLine("Entered");
var result = imageProvider.BeginGetImage(callback, image);
}
}
catch (Exception exc)
{
Console.WriteLine(exc.ToString());
// TODO: Do Something here.
}
}
/// <summary>
/// Adds a thumbnail to the Browser
/// </summary>
/// <param name="result">an async result used for retrieving state data from the load task.</param>
private void AddThumbnail(IAsyncResult result)
{
lock (Thumbnails)
{
try
{
Stream image = imageProvider.EndGetImage(result);
string filename = imageProvider.GetImageName(result);
string imagePath = imageProvider.GetImagePath(result);
var imageviewmodel = new AiImageThumbnailViewModel(image, filename, imagePath);
thumbnailHash[imagePath] = imageviewmodel;
HostInvoke(() => Thumbnails.Add(imageviewmodel));
UpdateChildZoom();
//synchMutex.ReleaseMutex();
Console.WriteLine("Exited");
}
catch (Exception exc)
{
Console.WriteLine(exc.ToString());
// TODO: Do Something here.
}
}
}
*笑*是的,这是屠杀的结果。 执行如下: 用户界面调用开始布局,一旦命中任务,它返回。 该任务应该处理文件夹。我不确定为什么要有Parallel.ForEach,一个简单的forEach就足够了。 O_O一定是我甩掉代码的遗留物。 就是这样,只有AddThumbnail的一个实例应该一次运行它的关键部分。 – Firoso 2010-03-15 22:34:01