如何在 ASP.NET 中使用 ConcurrentDictionary 和 Task

Question

我遇到了一些问题，其中 projectLogDict 没有更新 ImageCount。如果您查看下面的代码，我将 var drawingCount 和 var imageCount 添加到 Task.WhenAll.

问题是 imageCount 值似乎从未在 projectLogDict 中更新过。但是，如果我注释掉 var drawingCount，imageCount 值有效并在 projectLogDict

中更新

我不确定为什么不能在 projectLogDict 中更新两个值。

有没有办法同时更新 drawingCount 和 imageCount 并将其添加到 projectLogDict？

public async Task<ConcurrentDictionary<string, ProjectLogs>> GetProjectFiles(ConcurrentDictionary<string, ProjectLogs> projectLogDict)
{
    var locations = await _test.GetAllLocations().ConfigureAwait(false);
    foreach(var branch in locations)
    {
        var projects = await _test.GetLocationProjectsAsync(branch).ConfigureAwait(false);

        var task = new List<Task<ConcurrentDictionary<string, ProjectLogs>>>();
        var taskTwo = new List<Task<ConcurrentDictionary<string, ProjectLogs>>>();

        foreach (var project in projects)
        {
            var drawingCount = GetDrawingCount(project.Id);
            var imageCount = GetImageCount(project.Id);
            taskTwo.Add(imageCount);
            task.Add(drawingCount);

        }

        var x = await Task.WhenAll(task.ToArray()).ConfigureAwait(false);
        var y = await Task.WhenAll(taskTwo.ToArray()).ConfigureAwait(false);
    }

    return projectLogDict;
}



public async Task<ConcurrentDictionary<string, ProjectLogs>> GetImageCount(string projectId)
{
    var files = await _test.GetUploadFilesAsync(projectId, null).ConfigureAwait(false);
    projectLogDict.AddOrUpdate(projectId, new ProjectLogs { ImageCount = file.count() }, (key, value) => value = new ProjectLogs { ImageCount = file.count() });
    
    return projectLogDict;
}



public async Task<ConcurrentDictionary<string, ProjectLogs>> GetDrawingCount(string projectId )
{
    
    var drawingCount = await _test.GetItemsDrawing(projectId).ConfigureAwait(false);
    projectLogDict.AddOrUpdate(projectId, new ProjectLogs { DrawingCount = drawingCount.Count() }, (key, value) => value = new ProjectLogs { DrawingCount = drawingCount.Count() });
    
    return projectLogDict;
    
}

Answer 1

当第二个AddOrUpdate运行s时，如果不会Add因为projectId键已经存在，所以会运行updateValueFactory代表。这就是你的问题所在。对于这两个调用，您只设置一个属性，返回新的 class，这意味着您不断地覆盖字典中已有的内容。

要解决这个问题，您需要在委托中考虑 value 并设置相应的属性 :

projectLogDict.AddOrUpdate(projectId, new ProjectLogs { ImageCount = file.count() }, (key, value) => new ProjectLogs { ImageCount = file.count(), DrawingCount = value.DrawingCount });

和

projectLogDict.AddOrUpdate(projectId, new ProjectLogs { DrawingCount = drawingCount.Count() }, (key, value) => new ProjectLogs { DrawingCount = drawingCount.Count(), ImageCount = value.ImageCount });

如何在 ASP.NET 中使用 ConcurrentDictionary 和 Task

How to use ConcurrentDictionary and Task in ASP.NET

c#

asp.net

asynchronous

task