C# CodeFixes.CodeFixContext类代码示例

		public async override Task RegisterCodeFixesAsync(CodeFixContext context)
		{
			var document = context.Document;
			var cancellationToken = context.CancellationToken;
			var diagnostics = context.Diagnostics;
			var root = await document.GetSyntaxRootAsync(cancellationToken);
			var diagnostic = diagnostics.First();
			var node = root.FindNode(context.Span) as BinaryExpressionSyntax;
			if (node == null)
				return;
			StatementSyntax expression = null;
			var ifStatement = node.Parent as IfStatementSyntax;
			if (ifStatement == null)
				return;
            var statement = ifStatement.Statement;
			if (statement is BlockSyntax)
				expression = ((BlockSyntax)statement).Statements[0];
			else
				expression = statement;

			if (expression == null)
				return;

			context.RegisterCodeFix(CodeAction.Create("Remove redundant check", async token => {
				var editor = await DocumentEditor.CreateAsync(document, cancellationToken);
				expression = expression
					.WithOrderedTriviaFromSubTree(ifStatement)
					.WithAdditionalAnnotations(Formatter.Annotation);
                editor.ReplaceNode(ifStatement, expression);
				return editor.GetChangedDocument();
			}, string.Empty), diagnostic);
		}

        /// <inheritdoc/>
        public override async Task RegisterCodeFixesAsync(CodeFixContext context)
        {
            var document = context.Document;
            var root = await document.GetSyntaxRootAsync(context.CancellationToken).ConfigureAwait(false);

            foreach (var diagnostic in context.Diagnostics)
            {
                if (!diagnostic.Id.Equals(SA1309FieldNamesMustNotBeginWithUnderscore.DiagnosticId))
                {
                    continue;
                }

                var token = root.FindToken(diagnostic.Location.SourceSpan.Start);
                if (token.IsMissing)
                {
                    continue;
                }

                if (!string.IsNullOrEmpty(token.ValueText))
                {
                    var newName = token.ValueText.TrimStart(new[] { '_' });

                    if (string.IsNullOrEmpty(newName))
                    {
                        // The variable consisted of only underscores. In this case we cannot
                        // generate a valid variable name and thus will not offer a code fix.
                        continue;
                    }

                    context.RegisterCodeFix(CodeAction.Create(string.Format(NamingResources.SA1309CodeFix, newName), cancellationToken => RenameHelper.RenameSymbolAsync(document, root, token, newName, cancellationToken), equivalenceKey: nameof(SA1309CodeFixProvider)), diagnostic);
                }
            }
        }

    public async Task VerifyGetFixesWhenUsingSystemDoesNotExist()
    {
      var code = File.ReadAllText(
        [email protected]"Targets\{nameof(IsBusinessObjectSerializableMakeSerializableCodeFixTests)}.{(nameof(this.VerifyGetFixesWhenUsingSystemDoesNotExist))}.cs");
      var document = TestHelpers.Create(code);
      var tree = await document.GetSyntaxTreeAsync();
      var diagnostics = await TestHelpers.GetDiagnosticsAsync(code, new IsBusinessObjectSerializableAnalyzer());
      var sourceSpan = diagnostics[0].Location.SourceSpan;

      var actions = new List<CodeAction>();
      var codeActionRegistration = new Action<CodeAction, ImmutableArray<Diagnostic>>(
        (a, _) => { actions.Add(a); });

      var fix = new IsBusinessObjectSerializableMakeSerializableCodeFix();
      var codeFixContext = new CodeFixContext(document, diagnostics[0],
        codeActionRegistration, new CancellationToken(false));
      await fix.RegisterCodeFixesAsync(codeFixContext);

      Assert.AreEqual(2, actions.Count, nameof(actions.Count));

      await TestHelpers.VerifyActionAsync(actions,
        IsBusinessObjectSerializableMakeSerializableCodeFixConstants.AddSystemSerializableDescription, document,
        tree, $"{Environment.NewLine}[System.Serializable]");
      await TestHelpers.VerifyActionAsync(actions,
        IsBusinessObjectSerializableMakeSerializableCodeFixConstants.AddSerializableAndUsingDescription, document,
        tree, $"using System;{Environment.NewLine}{Environment.NewLine}[Serializable]");
    }

        public async override Task RegisterCodeFixesAsync(CodeFixContext context)
        {
            var document = context.Document;
            var cancellationToken = context.CancellationToken;
            var span = context.Span;
            var diagnostics = context.Diagnostics;
            var model = await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(false);
            if (model.IsFromGeneratedCode(cancellationToken))
                return;
            var root = await model.SyntaxTree.GetRootAsync(cancellationToken).ConfigureAwait(false);

            var diagnostic = diagnostics.First();
            var node = root.FindNode(context.Span);
            context.RegisterCodeFix(CodeActionFactory.Create(
                node.Span,
                diagnostic.Severity,
                GettextCatalog.GetString("Add 'new' modifier"),
                token =>
                {
                    SyntaxNode newRoot;
                    if (node.Kind() != SyntaxKind.VariableDeclarator)
                        newRoot = root.ReplaceNode(node, AddNewModifier(node));
                    else //this one wants to be awkward - you can't add modifiers to a variable declarator
                    {
                        SyntaxNode declaringNode = node.Parent.Parent;
                        if (declaringNode is FieldDeclarationSyntax)
                            newRoot = root.ReplaceNode(node.Parent.Parent, (node.Parent.Parent as FieldDeclarationSyntax).AddModifiers(SyntaxFactory.Token(SyntaxKind.NewKeyword)));
                        else //it's an event declaration
                            newRoot = root.ReplaceNode(node.Parent.Parent, (node.Parent.Parent as EventFieldDeclarationSyntax).AddModifiers(SyntaxFactory.Token(SyntaxKind.NewKeyword)));
                    }
                    return Task.FromResult(document.WithSyntaxRoot(newRoot.WithAdditionalAnnotations(Formatter.Annotation)));
                }), diagnostic);
        }

		public async Task GetFixes()
		{
			var code =
@"using System.ServiceModel;

public class AClass
{
	[OperationContract(IsOneWay = true)]
	public string AMethod() { return string.Empty; }
}";

			var document = TestHelpers.Create(code);
			var tree = await document.GetSyntaxTreeAsync();
			var diagnostics = await TestHelpers.GetDiagnosticsAsync(
				code, new IsOneWayOperationAnalyzer());
			var sourceSpan = diagnostics[0].Location.SourceSpan;

			var actions = new List<CodeAction>();
			var codeActionRegistration = new Action<CodeAction, ImmutableArray<Diagnostic>>(
			  (a, _) => { actions.Add(a); });

			var fix = new IsOneWayOperationMakeIsOneWayFalseCodeFix();
			var codeFixContext = new CodeFixContext(document, diagnostics[0],
			  codeActionRegistration, new CancellationToken(false));
			await fix.RegisterCodeFixesAsync(codeFixContext);

			Assert.Equal(1, actions.Count);

			await TestHelpers.VerifyActionAsync(actions,
			  IsOneWayOperationMakeIsOneWayFalseCodeFixConstants.Description, document,
			  tree, new[] { "fals" });
		}

        /// <inheritdoc/>
        public override async Task RegisterCodeFixesAsync(CodeFixContext context)
        {
            var root = await context.Document.GetSyntaxRootAsync(context.CancellationToken).ConfigureAwait(false);
            foreach (var diagnostic in context.Diagnostics)
            {
                SyntaxNode node = root.FindNode(diagnostic.Location.SourceSpan, getInnermostNodeForTie: true);
                if (node == null || node.IsMissing)
                {
                    continue;
                }

                SyntaxNode declarationNode = FindParentDeclarationNode(node);
                if (declarationNode == null)
                {
                    continue;
                }

                context.RegisterCodeFix(
                    CodeAction.Create(
                        MaintainabilityResources.SA1400CodeFix,
                        cancellationToken => GetTransformedDocumentAsync(context.Document, root, declarationNode),
                        nameof(SA1400CodeFixProvider)),
                    diagnostic);
            }
        }

        /// <inheritdoc/>
        public override async Task RegisterCodeFixesAsync(CodeFixContext context)
        {
            foreach (var diagnostic in context.Diagnostics)
            {
                var documentRoot = await context.Document.GetSyntaxRootAsync(context.CancellationToken).ConfigureAwait(false);
                SyntaxNode syntax = documentRoot.FindNode(diagnostic.Location.SourceSpan, findInsideTrivia: true, getInnermostNodeForTie: true);
                if (syntax == null)
                {
                    continue;
                }

                XmlElementSyntax xmlElementSyntax = syntax as XmlElementSyntax;
                if (xmlElementSyntax == null)
                {
                    // We continue even for placeholders if they are empty elements (XmlEmptyElementSyntax)
                    continue;
                }

                if (string.IsNullOrWhiteSpace(xmlElementSyntax.Content.ToString()))
                {
                    // The placeholder hasn't been updated yet.
                    continue;
                }

                context.RegisterCodeFix(
                    CodeAction.Create(
                        DocumentationResources.SA1651CodeFix,
                        cancellationToken => this.GetTransformedDocumentAsync(context.Document, xmlElementSyntax, cancellationToken),
                        nameof(SA1651CodeFixProvider)),
                    diagnostic);
            }
        }

 public sealed override Task RegisterCodeFixesAsync(CodeFixContext context)
 {
     var diagnostic = context.Diagnostics.First();
     context.RegisterCodeFix(CodeAction.Create(
         "Removes redundant comparision", c => RemoveRedundantComparisonAsync(context.Document, diagnostic, c), nameof(SimplifyRedundantBooleanComparisonsCodeFixProvider)), diagnostic);
     return Task.FromResult(0);
 }

        public override sealed async Task RegisterCodeFixesAsync(CodeFixContext context)
        {
            var root = await context.Document.GetSyntaxRootAsync(context.CancellationToken).ConfigureAwait(false);

            var diagnostic = context.Diagnostics.First();
            var diagnosticSpan = diagnostic.Location.SourceSpan;
            var syntaxNode = root.FindNode(diagnosticSpan, getInnermostNodeForTie: true);

            var statement = syntaxNode as StatementSyntax;
            var assignment = syntaxNode as AssignmentExpressionSyntax;
            var binary = syntaxNode as BinaryExpressionSyntax;
            if (statement != null ||
                assignment != null ||
                binary != null)
            {
                context.RegisterCodeFix(
                    CodeAction.Create(
                        Title,
                        c =>
                        {
                            var newRoot = CalculateNewRoot(root, diagnostic, statement, assignment, binary);
                            return Task.FromResult(context.Document.WithSyntaxRoot(newRoot));
                        }),
                    context.Diagnostics);
            }
        }

 public override sealed Task RegisterCodeFixesAsync(CodeFixContext context)
 {
     var diagnostic = context.Diagnostics.First();
     if (diagnostic.Properties["kind"] == "missingDoc")
         context.RegisterCodeFix(CodeAction.Create(Resources.XmlDocumentationCreateMissingParametersCodeFixProvider_Title, c => FixParametersAsync(context.Document, diagnostic, c)), diagnostic);
     return Task.FromResult(0);
 }

        public override sealed async Task RegisterCodeFixesAsync(CodeFixContext context)
        {
            var root = await context.Document.GetSyntaxRootAsync(context.CancellationToken).ConfigureAwait(false);
            var diagnostic = context.Diagnostics.First();
            var diagnosticSpan = diagnostic.Location.SourceSpan;
            var initializer = root.FindNode(diagnosticSpan) as ConstructorInitializerSyntax;
            if (initializer == null)
            {
                return;
            }

            var constructor = initializer.Parent as ConstructorDeclarationSyntax;
            if (constructor == null)
            {
                return;
            }

            context.RegisterCodeFix(
                CodeAction.Create(
                    Title,
                    c =>
                    {
                        var newRoot = RemoveInitializer(root, constructor);
                        return Task.FromResult(context.Document.WithSyntaxRoot(newRoot));
                    }),
                context.Diagnostics);
        }

 private void AddFix(string codeFixTitle, CodeFixContext context, SyntaxNode root, SyntaxNode classDecl, SyntaxGenerator generator, params string[] languages)
 {
     var fix = new MyCodeAction(
         codeFixTitle,
         c => GetFix(context.Document, root, classDecl, generator, languages));
     context.RegisterCodeFix(fix, context.Diagnostics);
 }

        public sealed override async Task RegisterCodeFixesAsync(CodeFixContext context)
        {
            var root = await context.Document.GetSyntaxRootAsync(context.CancellationToken).ConfigureAwait(false);
            var token = root.FindToken(context.Span.Start);
            if (!token.Span.IntersectsWith(context.Span))
            {
                return;
            }

            var generator = SyntaxGenerator.GetGenerator(context.Document);
            var classDecl = generator.GetDeclaration(token.Parent);
            if (classDecl == null)
            {
                return;
            }

            // Register fixes.

            // 1) Apply C# DiagnosticAnalyzerAttribute.
            var title = string.Format(CodeAnalysisDiagnosticsResources.ApplyDiagnosticAnalyzerAttribute_1, LanguageNames.CSharp);
            AddFix(title, context, root, classDecl, generator, LanguageNames.CSharp);

            // 2) Apply VB DiagnosticAnalyzerAttribute.
            title = string.Format(CodeAnalysisDiagnosticsResources.ApplyDiagnosticAnalyzerAttribute_1, LanguageNames.VisualBasic);
            AddFix(title, context, root, classDecl, generator, LanguageNames.VisualBasic);

            // 3) Apply both C# and VB DiagnosticAnalyzerAttributes.
            title = string.Format(CodeAnalysisDiagnosticsResources.ApplyDiagnosticAnalyzerAttribute_2, LanguageNames.CSharp, LanguageNames.VisualBasic);
            AddFix(title, context, root, classDecl, generator, LanguageNames.CSharp, LanguageNames.VisualBasic);
        }

        public override async Task RegisterCodeFixesAsync(CodeFixContext context)
        {
            var syntaxFactoryService = SyntaxGenerator.GetGenerator(context.Document);
            var root = await context.Document.GetSyntaxRootAsync(context.CancellationToken).ConfigureAwait(false);
            var node = root.FindNode(context.Span);

            // We cannot have multiple overlapping diagnostics of this id.
            var diagnostic = context.Diagnostics.Single();

            if (IsInArgumentContext(node))
            {
                // StringComparison.CurrentCulture => StringComparison.Ordinal
                // StringComparison.CurrentCultureIgnoreCase => StringComparison.OrdinalIgnoreCase
                context.RegisterCodeFix(new MyCodeAction(SystemRuntimeAnalyzersResources.UseOrdinalStringComparisonTitle,
                                                         async ct => await FixArgument(context.Document, syntaxFactoryService, root, node).ConfigureAwait(false)),
                                                    diagnostic);
            }
            else if (IsInIdentifierNameContext(node))
            {
                // string.Equals(a, b) => string.Equals(a, b, StringComparison.Ordinal)
                // string.Compare(a, b) => string.Compare(a, b, StringComparison.Ordinal)
                context.RegisterCodeFix(new MyCodeAction(SystemRuntimeAnalyzersResources.UseOrdinalStringComparisonTitle,
                                                         async ct => await FixIdentifierName(context.Document, syntaxFactoryService, root, node, context.CancellationToken).ConfigureAwait(false)),
                                                    diagnostic);
            }
            else if (IsInEqualsContext(node))
            {
                // "a == b" => "string.Equals(a, b, StringComparison.Ordinal)"
                // "a != b" => "!string.Equals(a, b, StringComparison.Ordinal)"
                context.RegisterCodeFix(new MyCodeAction(SystemRuntimeAnalyzersResources.UseOrdinalStringComparisonTitle,
                                async ct => await FixEquals(context.Document, syntaxFactoryService, root, node, context.CancellationToken).ConfigureAwait(false)),
                        diagnostic);
            }
        }

        public override async Task RegisterCodeFixesAsync(CodeFixContext context)
        {
            var root = await context.Document.GetSyntaxRootAsync(context.CancellationToken).ConfigureAwait(false);

            var model = await context.Document.GetSemanticModelAsync(context.CancellationToken).ConfigureAwait(false);

            var declaration = root.FindNode(context.Span);
            if (declaration == null)
            {
                return;
            }

            // find a Dispose method
            var iDisposableType = model.Compilation.GetSpecialType(SpecialType.System_IDisposable);
            var iDisposable_Dispose = (iDisposableType?.GetMembers(DisposableFieldsShouldBeDisposedAnalyzer.Dispose))?.Single();
            if (iDisposableType == null || iDisposable_Dispose == null)
            {
                return;
            }

            var fieldSymbol = model.GetDeclaredSymbol(declaration, context.CancellationToken) as IFieldSymbol;
            var disposeMethod = fieldSymbol?.ContainingType?.FindImplementationForInterfaceMember(iDisposable_Dispose) as IMethodSymbol;
            if (disposeMethod == null)
            {
                return;
            }

            // We cannot have multiple overlapping diagnostics of this id.
            var diagnostic = context.Diagnostics.Single();

            context.RegisterCodeFix(new MyCodeAction(SystemRuntimeAnalyzersResources.DisposableFieldsShouldBeDisposedMessage,
                                                     async ct => await AddDisposeCall(context.Document, declaration, fieldSymbol, disposeMethod, iDisposableType, iDisposable_Dispose, ct).ConfigureAwait(false)),
                                    diagnostic);
        }