public async Task <List <string> > IterateFolders(string folderName, string searchString, CancellationToken token)
{
var foundList = new List <string>();
if (!Directory.Exists(folderName))
{
OnIterate?.Invoke(new MonitorProgressArgs("Folder does not exists!"));
_folderFound = false;
return(foundList);
}
_folderFound = true;
var currentFileName = "";
try
{
foreach (var fileName in Directory.EnumerateFiles(folderName, "*.txt", SearchOption.AllDirectories))
{
currentFileName = fileName;
OnIterate?.Invoke(new MonitorProgressArgs(fileName));
var contents = File.ReadAllText(fileName);
await Task.Delay(1, token);
if (contents.Contains(searchString))
{
foundList.Add(fileName);
}
if (token.IsCancellationRequested)
{
token.ThrowIfCancellationRequested();
}
}
}
catch (Exception ex)
{
OnIterate?.Invoke(new MonitorProgressArgs($"Access denied {currentFileName}"));
}
return(foundList);
}
/// <summary>
/// Run a long running task composed of small awaited and configured tasks
/// Using ConfigureAwait(false) makes this particular method run a bit faster
/// then the example above.
/// </summary>
public async Task <int> ProcessAsync2(int loop, CancellationToken ct)
{
int index = 0;
for (int i = 0; i < loop; i++)
{
Console.WriteLine(SynchronizationContext.Current == null);
await Task.Delay(10, ct).ConfigureAwait(false);
OnIterate?.Invoke(this, new ProcessIndexingArgs(index));
if (ct.IsCancellationRequested)
{
ct.ThrowIfCancellationRequested();
}
index += i;
}
return(index);
}
/// <summary>
/// In this example each time await is called we go back to the captured
/// context after the execution of the awaited task.
///
/// Calling ConfigureAwait(false) after the task means that we do not care
/// if the code after the await, runs on the captured context or not.
/// </summary>
/// <param name="loop"></param>
/// <param name="ct">Valid cancellation token</param>
/// <returns></returns>
public async Task <int> ProcessAsync1(int loop, CancellationToken ct)
{
var result = 0;
for (var index = 0; index < loop; index++)
{
Console.WriteLine(SynchronizationContext.Current == null);
await Task.Delay(10, ct);
OnIterate?.Invoke(this, new ProcessIndexingArgs(index));
if (ct.IsCancellationRequested)
{
ct.ThrowIfCancellationRequested();
}
result += index;
}
return(result);
}