/// <summary>
/// 检查是否下载完成
/// </summary>
/// <param name="speedCalculator"></param>
/// <param name="cancellationToken"></param>
/// <returns></returns>
private async Task <int> CheckDownloadInfoAsync(SpeedCalculator speedCalculator, CancellationToken cancellationToken)
{
var retryTasks = new List <DownloadTask>();
var retryCount = 0;
int errorCount = 0;
Func <DownloadSegmentInfo, bool> predicate = GetCheckDownloadSegmentInfoFunc();
while ((errorCount = DownloadInfo.Count(predicate)) > 0)
{
if (retryCount >= 3)
{
break;
}
Console.WriteLine($"错误数据个数:{errorCount},开始第{retryCount}次重试");
foreach (var item in DownloadInfo)
{
if (predicate(item))
{
item.SrcStream = null;
var task = DownloadSegmentFileAsync(item, (r, percentage) =>
{
speedCalculator.CurrentValue += r;
}, cancellationToken);
retryTasks.Add(task);
}
}
await retryTasks.StartAndWaitAllThrottled(MaxThreadCount);
retryCount++;
}
return(errorCount);
}
/// <summary>
/// 下载文件
/// </summary>
/// <param name="progressAction"></param>
/// <param name="cancellationToken"></param>
/// <returns></returns>
public async Task DownloadFileAsync(Action <ProgressInfo> progressAction, CancellationToken cancellationToken = default)
{
if (IsDownloaded)
{
return;
}
SpeedCalculator speedCalculator = new SpeedCalculator();
ProgressInfo progressInfo = new ProgressInfo();
bool isCompleted = false;
speedCalculator.Updated += async(h) =>
{
progressInfo.AverageSpeed = speedCalculator.AverageSpeed;
progressInfo.CurrentValue = speedCalculator.CurrentValue;
progressInfo.Speed = speedCalculator.Speed;
progressInfo.Percentage = DownloadInfo.Percentage;
progressInfo.TargetValue = DownloadInfo?.Size;
progressAction.Invoke(progressInfo);
var count = DownloadInfo.Count(m => m.Size == 0);
//Console.WriteLine("count " + count + " size " + DownloadInfo.Size + " read size " + DownloadInfo.TotalReadBytes);
if (isCompleted)
{
speedCalculator.Stop();
}
else
{
await SaveDownloadInfoAsync();
}
};
foreach (var segment in DownloadInfo)
{
if (segment.TotalReadBytes != 0 && segment.TotalReadBytes >= segment.Size)
{
continue;
}
var task = DownloadSegmentFileAsync(segment, (r, percentage) =>
{
speedCalculator.CurrentValue += r;
}, cancellationToken);
FileSegmentaionTasks.Add(task);
}
speedCalculator.Start();
await FileSegmentaionTasks.StartAndWaitAllThrottled(MaxThreadCount);
var errorCount = await CheckDownloadInfoAsync(speedCalculator, cancellationToken);
///错误数量
if (errorCount == 0)
{
await ReconstructSegmentsAsync();
await CompleteAsync(true);
}
isCompleted = true;
}
