private async Task RunDownloadParallelAsync(IProgress <ProgressModel> progress, ParallelOptions parallelOption)
{
var websites = SiteData();
int count = 1;
ProgressModel model = new ProgressModel();
await Task.Run(() => {
try {
ParallelLoopResult result = Parallel.ForEach <string>(websites, parallelOption, (site, loopState) => {
if (parallelOption.CancellationToken.IsCancellationRequested)
{
this.Dispatcher.Invoke(() => {
resultsWindow.Text += $"The download was cancelled : {Environment.NewLine}";
});
return;
}
if (loopStatus == "stop")
{
loopState.Stop();
return;
}
else if (loopStatus == "break")
{
loopState.Break();
return;
}
var results = DownloadWebsite(site);
model.PercentageComplete = (count * 100) / websites.Count;
progress.Report(model);
count++;
this.Dispatcher.Invoke(() => {
resultsWindow.Text += $"{results.WebsiteUrl} downloaded: {results.WebsiteData.Length}" +
$" characters long. {Environment.NewLine}";
});
});
if (result.IsCompleted)
{
this.Dispatcher.Invoke(() => {
resultsWindow.Text += "Stack ran to completion" + $" {Environment.NewLine}";
});
}
else if (result.IsCompleted == false && result.LowestBreakIteration == null)
{
//Loop exited prematurely by Stop()
this.Dispatcher.Invoke(() => {
resultsWindow.Text += "Stack exited by Stop()." + $" {Environment.NewLine}";
loopStatus = "non";
});
}
else if (result.IsCompleted == false && result.LowestBreakIteration != null)
{
//Loop exited by Break()
this.Dispatcher.Invoke(() => {
resultsWindow.Text += "Stack exited by Break()." + $"{Environment.NewLine}";
loopStatus = "non";
});
}
} catch (OperationCanceledException) {
this.Dispatcher.Invoke(() => {
resultsWindow.Text += $"The download was cancelled : {Environment.NewLine}";
});
} finally {
cts.Dispose();
cts = new CancellationTokenSource();
}
});
}
private void ReportProgress(object sender, ProgressModel e)
{
executeProgress.Value = e.PercentageComplete;
}