C# Threading.CancellationToken类代码示例

        protected override async Task<List<MediaSourceInfo>> GetChannelStreamMediaSources(TunerHostInfo info, string channelId, CancellationToken cancellationToken)
        {
            var urlHash = info.Url.GetMD5().ToString("N");
            var prefix = ChannelIdPrefix + urlHash;
            if (!channelId.StartsWith(prefix, StringComparison.OrdinalIgnoreCase))
            {
                return null;
            }

            var channels = await GetChannels(info, true, cancellationToken).ConfigureAwait(false);
            var m3uchannels = channels.Cast<M3UChannel>();
            var channel = m3uchannels.FirstOrDefault(c => string.Equals(c.Id, channelId, StringComparison.OrdinalIgnoreCase));
            if (channel != null)
            {
                var path = channel.Path;
                MediaProtocol protocol = MediaProtocol.File;
                if (path.StartsWith("http", StringComparison.OrdinalIgnoreCase))
                {
                    protocol = MediaProtocol.Http;
                }
                else if (path.StartsWith("rtmp", StringComparison.OrdinalIgnoreCase))
                {
                    protocol = MediaProtocol.Rtmp;
                }
                else if (path.StartsWith("rtsp", StringComparison.OrdinalIgnoreCase))
                {
                    protocol = MediaProtocol.Rtsp;
                }

                var mediaSource = new MediaSourceInfo
                {
                    Path = channel.Path,
                    Protocol = protocol,
                    MediaStreams = new List<MediaStream>
                    {
                        new MediaStream
                        {
                            Type = MediaStreamType.Video,
                            // Set the index to -1 because we don't know the exact index of the video stream within the container
                            Index = -1,
                            IsInterlaced = true
                        },
                        new MediaStream
                        {
                            Type = MediaStreamType.Audio,
                            // Set the index to -1 because we don't know the exact index of the audio stream within the container
                            Index = -1

                        }
                    },
                    RequiresOpening = false,
                    RequiresClosing = false,

                    ReadAtNativeFramerate = true
                };

                return new List<MediaSourceInfo> { mediaSource };
            }
            return new List<MediaSourceInfo>();
        }

        internal async Task RemoveAllRenameAnnotationsAsync(IEnumerable<DocumentId> documentWithRenameAnnotations, AnnotationTable<RenameAnnotation> annotationSet, CancellationToken cancellationToken)
        {
            foreach (var documentId in documentWithRenameAnnotations)
            {
                if (_renamedSpansTracker.IsDocumentChanged(documentId))
                {
                    var document = _newSolution.GetDocument(documentId);
                    var root = await document.GetSyntaxRootAsync(cancellationToken).ConfigureAwait(false);

                    // For the computeReplacementToken and computeReplacementNode functions, use 
                    // the "updated" node to maintain any annotation removals from descendants.
                    var newRoot = root.ReplaceSyntax(
                        nodes: annotationSet.GetAnnotatedNodes(root),
                        computeReplacementNode: (original, updated) => annotationSet.WithoutAnnotations(updated, annotationSet.GetAnnotations(updated).ToArray()),
                        tokens: annotationSet.GetAnnotatedTokens(root),
                        computeReplacementToken: (original, updated) => annotationSet.WithoutAnnotations(updated, annotationSet.GetAnnotations(updated).ToArray()),
                        trivia: SpecializedCollections.EmptyEnumerable<SyntaxTrivia>(),
                        computeReplacementTrivia: null);

                    _intermediateSolutionContainingOnlyModifiedDocuments = _intermediateSolutionContainingOnlyModifiedDocuments.WithDocumentSyntaxRoot(documentId, newRoot, PreservationMode.PreserveIdentity);
                }
            }

            _newSolution = _intermediateSolutionContainingOnlyModifiedDocuments;
        }

        public async Task<bool> PeekAsync(CancellationToken cancellationToken)
        {
            //If we already have a byte read but not consumed, do nothing.
            if (_hasPeekByte)
            {
                return true;
            }

            //If transport closed we can't peek.
            if (!IsOpen)
            {
                return false;
            }

            //Try to read one byte. If succeeds we will need to store it for the next read.
            try
            {
                var bytes = await ReadAsync(_peekBuffer, 0, 1, cancellationToken);
                if (bytes == 0)
                {
                    return false;
                }
            }
            catch (IOException)
            {
                return false;
            }

            _hasPeekByte = true;
            return true;
        }

        public async Task Start(CancellationToken token)
        {
            while (!token.IsCancellationRequested)
            {
                Settings.Default.Reload();
                var imageInfo = GetLatestImageInfo();
                if (imageInfo != null)
                {
                    var image = AssembleImageFrom(imageInfo);
                    var imageFile = SaveImage(image);
                    Wallpaper.Set(imageFile, Wallpaper.Style.Fit);
                }

                if (Settings.Default.Interval > 0)
                {
                    _internalTokenSource = new CancellationTokenSource();
                    using (var linkedCts = CancellationTokenSource.CreateLinkedTokenSource(_internalTokenSource.Token, token))
                    {
                        try
                        {
                            await Task.Delay(TimeSpan.FromMinutes(Settings.Default.Interval), linkedCts.Token);
                        }
                        catch
                        {
                            // ignore exception raised by token cancellation
                        }
                    }
                }
            }
        }

        public async Task Run(IProgress<double> progress, CancellationToken cancellationToken)
        {
            var users = _userManager.Users
                .DistinctBy(ChannelDownloadScheduledTask.GetUserDistinctValue)
                .Select(i => i.Id.ToString("N"))
                .ToList();

            var numComplete = 0;

            foreach (var user in users)
            {
                double percentPerUser = 1;
                percentPerUser /= users.Count;
                var startingPercent = numComplete * percentPerUser * 100;

                var innerProgress = new ActionableProgress<double>();
                innerProgress.RegisterAction(p => progress.Report(startingPercent + (percentPerUser * p)));

                await DownloadContent(user, cancellationToken, innerProgress).ConfigureAwait(false);

                numComplete++;
                double percent = numComplete;
                percent /= users.Count;
                progress.Report(percent * 100);
            }

            progress.Report(100);
        }

        private async Task VerifyFixInternalAsync(string language, ImmutableArray<DiagnosticAnalyzer> analyzers, CodeFixProvider codeFixProvider, string oldSource, string newSource, int? codeFixIndex,
            bool allowNewCompilerDiagnostics, int maxNumberOfIterations, Func<ImmutableArray<DiagnosticAnalyzer>, CodeFixProvider, int?, CancellationToken, Document, int, Task<Document>> getFixedDocument, CancellationToken cancellationToken)
        {
            var document = this.CreateDocument(oldSource, language);
            var compilerDiagnostics = await GetCompilerDiagnosticsAsync(document, cancellationToken).ConfigureAwait(false);

            document = await getFixedDocument(analyzers, codeFixProvider, codeFixIndex, cancellationToken, document, maxNumberOfIterations).ConfigureAwait(false);

            var newCompilerDiagnostics = GetNewDiagnostics(compilerDiagnostics, await GetCompilerDiagnosticsAsync(document, cancellationToken).ConfigureAwait(false));

            // check if applying the code fix introduced any new compiler diagnostics
            if (!allowNewCompilerDiagnostics && newCompilerDiagnostics.Any())
            {
                // Format and get the compiler diagnostics again so that the locations make sense in the output
                document = await Formatter.FormatAsync(document, Formatter.Annotation, cancellationToken: cancellationToken).ConfigureAwait(false);
                newCompilerDiagnostics = GetNewDiagnostics(compilerDiagnostics, await GetCompilerDiagnosticsAsync(document, cancellationToken).ConfigureAwait(false));

                string message =
                    string.Format("Fix introduced new compiler diagnostics:\r\n{0}\r\n\r\nNew document:\r\n{1}\r\n",
                        string.Join("\r\n", newCompilerDiagnostics.Select(d => d.ToString())),
                        (await document.GetSyntaxRootAsync(cancellationToken).ConfigureAwait(false)).ToFullString());
                Assert.True(false, message);
            }

            // after applying all of the code fixes, compare the resulting string to the inputted one
            var actual = await GetStringFromDocumentAsync(document, cancellationToken).ConfigureAwait(false);
            Assert.Equal(newSource, actual);
        }

 public override Task ExecuteBindingAsync(Controllers.HttpActionContext actionContext, CancellationToken cancellationToken)
 {
     return _traceWriter.TraceBeginEndAsync(
         actionContext.ControllerContext.Request,
         TraceCategories.ModelBindingCategory,
         TraceLevel.Info,
         _innerBinding.GetType().Name,
         ExecuteBindingAsyncMethodName,
         beginTrace: null,
         execute: () => _innerBinding.ExecuteBindingAsync(actionContext, cancellationToken),
         endTrace: (tr) =>
         {
             if (!actionContext.ModelState.IsValid)
             {
                 tr.Message = Error.Format(SRResources.TraceModelStateInvalidMessage,
                                           FormattingUtilities.ModelStateToString(
                                                 actionContext.ModelState));
             }
             else
             {
                 if (actionContext.ActionDescriptor.GetParameters().Count > 0)
                 {
                     tr.Message = Error.Format(SRResources.TraceValidModelState,
                                               FormattingUtilities.ActionArgumentsToString(
                                                     actionContext.ActionArguments));
                 }
             }
         },
         errorTrace: null);
 }

        private static async Task<Document> MakeMock(Document document, SyntaxNode invokationSyntax,
            CancellationToken cancellationToken)
        {
            var testSemanticModel = await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(false);

            var testInitMethodDecl = TestSemanticHelper.GetTestInitializeMethod(testSemanticModel);

            var declaredFields = testInitMethodDecl.Parent.ChildNodes().OfType<FieldDeclarationSyntax>().ToArray();

            var suts = testInitMethodDecl.GetSuts(testSemanticModel, declaredFields);

            var memberAccessExpressions = invokationSyntax.DescendantNodes()
                .OfType<ExpressionSyntax>()
                .Where(x => x is InvocationExpressionSyntax || x is MemberAccessExpressionSyntax)
                .Select(expr =>
                {
                    var memberAccess = expr as MemberAccessExpressionSyntax;
                    var invokationExpression = expr as InvocationExpressionSyntax;
                    var expression = invokationExpression == null ? memberAccess : invokationExpression.Expression;
                    return expression;
                });

            var invokedMethodsOfMocks = memberAccessExpressions.SelectMany(expressionSyntax => MocksAnalyzingEngine.GetInvokedMethodsOfMock(expressionSyntax, testSemanticModel, suts))
                                                               .DistinctBy(x => string.Join(",", x.FieldsToSetup.SelectMany(y => y.Field.Select(z => z))) + "," + x.MethodOrPropertySymbol)
                                                               .ToArray();

            if (invokedMethodsOfMocks.Length == 0)
                return document;

            var editor = await DocumentEditor.CreateAsync(document, cancellationToken).ConfigureAwait(false);

            ChangesMaker.ApplyChanges(invokationSyntax, editor, invokedMethodsOfMocks);

            return editor.GetChangedDocument();
        }

    public override async Task OnAuthorizationAsync( HttpActionContext actionContext, CancellationToken cancellationToken )
    {

      if ( actionContext.ControllerContext.ControllerDescriptor.ControllerType == typeof( UserController ) || string.Equals( actionContext.ActionDescriptor.ActionName, "Test", StringComparison.OrdinalIgnoreCase ) )
        return;

      var request = actionContext.Request;

      string loginToken = null;

      if ( loginToken == null )
      {
        var authorization = request.Headers.Authorization;

        if ( authorization != null && authorization.Scheme == "Hello" )
          loginToken = authorization.Parameter;
      }

      if ( loginToken == null )
      {
        var cookie = request.Headers.GetCookies( "loginToken" ).SelectMany( c => c.Cookies );
        if ( cookie.Any() )
          loginToken = cookie.First().Value;

      }


      var userId = Host.UserService.GetUserID( loginToken );
      if ( userId == null )
        actionContext.Response = request.CreateErrorResponse( HttpStatusCode.Unauthorized, "Unauthorized" );

      else
        actionContext.Request.Properties["UserID"] = userId;
    }

        private static bool IsExtensionMethodParameterContext(CSharpSyntaxContext context, CancellationToken cancellationToken)
        {
            // TODO(cyrusn): lambda/anon methods can have out/ref parameters
            if (!context.SyntaxTree.IsParameterModifierContext(context.Position, context.LeftToken, cancellationToken, allowableIndex: 0))
            {
                return false;
            }

            var token = context.LeftToken;
            var method = token.GetAncestor<MethodDeclarationSyntax>();
            var typeDecl = method.GetAncestorOrThis<TypeDeclarationSyntax>();

            if (method == null || typeDecl == null)
            {
                return false;
            }

            if (typeDecl.Kind() != SyntaxKind.ClassDeclaration)
            {
                return false;
            }

            if (!method.Modifiers.Any(t => t.Kind() == SyntaxKind.StaticKeyword))
            {
                return false;
            }

            if (!typeDecl.Modifiers.Any(t => t.Kind() == SyntaxKind.StaticKeyword))
            {
                return false;
            }

            return true;
        }

		public async Task<IEnumerable<CodeAction>> GetRefactoringsAsync(Document document, TextSpan textSpan, CancellationToken cancellationToken)
		{
			var root = await document.GetSyntaxRootAsync(cancellationToken).ConfigureAwait(false);
			var node = root.FindNode(textSpan);
			var switchStatementNode = node as SwitchStatementSyntax;
			if (switchStatementNode == null)
				return null;

			var semanticModel = await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(false);

			var memberEx = switchStatementNode.Expression as MemberAccessExpressionSyntax;
			if (memberEx == null)
				return null;

			var symbolInfo = semanticModel.GetTypeInfo(memberEx.Name);
			var enumTypeInfo = symbolInfo.Type;
			if (enumTypeInfo.TypeKind != TypeKind.Enum)
				return null;

			var enumName = enumTypeInfo.Name;
			var nameSpace = enumTypeInfo.ContainingNamespace.Name;
			var enumType = Type.GetType(nameSpace + "." + enumName);
			if (enumType == null)
				return null;

			return new[] { CodeAction.Create("Explode Switch", c => ExplodeSwitch(document, root, semanticModel, switchStatementNode, c)) };
		}

        //probe==StartBounder
        public bool GeneratePasswords(int[] probe, int[] startBoundary, int[] endBoundary, int depth, int range, CancellationToken ct, CancellationTokenSource tokenSource, Action<string> sendPassword)
        {
            bool result = false;
            char[] probeChar = CharForThread(probe, _options);

            string probeString = String.Join("", probeChar);

            if (depth==0)
            {
                Console.WriteLine(probeString);
                if (VerifyMd5Hash(probeString))
                {
                    Password = probeString;
                    sendPassword(Password);
                    return true;
                }
                return false;
            }
            if (ct.IsCancellationRequested)
            {
                Console.WriteLine("Task is canceled");
            }

            if (probe.SequenceEqual(endBoundary)) return false;

            for (int i = 0; i < range; i++)
                {
                    probe[depth - 1] = i;
                    result = GeneratePasswords(probe, startBoundary, endBoundary, depth - 1, range, ct, tokenSource, sendPassword);
                    if (result) break;
                }
                return result;
        }

 protected override bool IsValidContext(int position, CSharpSyntaxContext context, CancellationToken cancellationToken)
 {
     return
         IsInstanceExpressionOrStatement(context) ||
         IsExtensionMethodParameterContext(context, cancellationToken) ||
         IsConstructorInitializerContext(context);
 }

		protected override bool TryInitializeState(
			Document document, SemanticModel model, SyntaxNode node, CancellationToken cancellationToken,
			out INamedTypeSymbol classType, out INamedTypeSymbol abstractClassType)
		{
			var baseClassNode = node as TypeSyntax;
			if (baseClassNode != null && baseClassNode.Parent is BaseTypeSyntax &&
				baseClassNode.Parent.IsParentKind(SyntaxKind.BaseList) &&
				((BaseTypeSyntax)baseClassNode.Parent).Type == baseClassNode)
			{
				if (baseClassNode.Parent.Parent.IsParentKind(SyntaxKind.ClassDeclaration))
				{
					abstractClassType = model.GetTypeInfo(baseClassNode, cancellationToken).Type as INamedTypeSymbol;
					cancellationToken.ThrowIfCancellationRequested();

					if (abstractClassType.IsAbstractClass())
					{
						var classDecl = baseClassNode.Parent.Parent.Parent as ClassDeclarationSyntax;
						classType = model.GetDeclaredSymbol(classDecl, cancellationToken) as INamedTypeSymbol;

						return classType != null && abstractClassType != null;
					}
				}
			}

			classType = null;
			abstractClassType = null;
			return false;
		}

        public async Task<Token> TokenAsync(string code, CancellationToken cancellationToken = default(CancellationToken))
        {
            var token = await _requestExecuter.Execute<Token>(() => _requestGenerator.AccessToken(_options.ClientId, _options.ClientSecret, _options.RedirectUri, code), cancellationToken: cancellationToken).ConfigureAwait(false);

            _options.AccessToken = token.access_token;
            return token;
        }