async Task <bool> BinarySearchFileAsync(string fileName, Searcher searcher, AnswerResult answer, IProgress <ProgressReport> progress, CancellationToken cancel)
{
try
{
if (answer.Answer == MessageOptions.Cancel)
{
return(true);
}
if (Directory.Exists(fileName))
{
return(false);
}
var findLen = searcher.MaxLen;
if (findLen == 0)
{
return(false);
}
var buffer = new byte[8192];
var used = 0;
using (var stream = File.OpenRead(fileName))
while (!cancel.IsCancellationRequested)
{
var block = await stream.ReadAsync(buffer, used, buffer.Length - used);
if (block == 0)
{
break;
}
used += block;
progress.Report(new ProgressReport(stream.Position, stream.Length));
var result = searcher.Find(buffer, 0, used, true);
if (result.Any())
{
return(true);
}
var keep = Math.Min(used, findLen - 1);
Array.Copy(buffer, used - keep, buffer, 0, keep);
used = keep;
}
return(false);
}
catch (Exception ex)
{
TabsParent.Dispatcher.Invoke(() =>
{
if ((answer.Answer != MessageOptions.YesToAll) && (answer.Answer != MessageOptions.NoToAll))
{
answer.Answer = new Message(WindowParent)
{
Title = "Confirm",
Text = $"Unable to read {fileName}.\n\n{ex.Message}\n\nLeave selected?",
Options = MessageOptions.YesNoYesAllNoAllCancel,
DefaultCancel = MessageOptions.Cancel,
}
}
.Show();
});
public List <Tuple <int, int> > StringMatches(Searcher searcher, int offset, int length)
{
return(searcher.Find(Data, offset, length));
}