C# VariableInitializer类代码示例

			public override void VisitVariableInitializer (VariableInitializer variableInitializer)
			{
				base.VisitVariableInitializer (variableInitializer);

				var resolveResult = ctx.Resolve (variableInitializer) as LocalResolveResult;
				CollectIssues (variableInitializer, variableInitializer.GetParent<BlockStatement> (), resolveResult);
			}

        protected void EmitEventAccessor(EventDeclaration e, VariableInitializer evtVar, bool add)
        {
            string name = evtVar.Name;

            this.Write(add ? "add" : "remove", name, " : ");
            this.WriteFunction();
            this.WriteOpenParentheses();
            this.Write("value");
            this.WriteCloseParentheses();
            this.WriteSpace();
            this.BeginBlock();
            this.WriteThis();
            this.WriteDot();
            this.Write(this.Emitter.GetEntityName(e));
            this.Write(" = ");
            this.Write(Bridge.Translator.Emitter.ROOT, ".", add ? Bridge.Translator.Emitter.DELEGATE_COMBINE : Bridge.Translator.Emitter.DELEGATE_REMOVE);
            this.WriteOpenParentheses();
            this.WriteThis();
            this.WriteDot();
            this.Write(this.Emitter.GetEntityName(e));
            this.WriteComma();
            this.WriteSpace();
            this.Write("value");
            this.WriteCloseParentheses();
            this.WriteSemiColon();
            this.WriteNewLine();
            this.EndBlock();
        }

		public void Run(AstNode node)
		{
			Run(node, null);
			// Declare all the variables at the end, after all the logic has run.
			// This is done so that definite assignment analysis can work on a single representation and doesn't have to be updated
			// when we change the AST.
			foreach (var v in variablesToDeclare) {
				if (v.ReplacedAssignment == null) {
					BlockStatement block = (BlockStatement)v.InsertionPoint.Parent;
					block.Statements.InsertBefore(
						v.InsertionPoint,
						new VariableDeclarationStatement((AstType)v.Type.Clone(), v.Name));
				}
			}
			// First do all the insertions, then do all the replacements. This is necessary because a replacement might remove our reference point from the AST.
			foreach (var v in variablesToDeclare) {
				if (v.ReplacedAssignment != null) {
					// We clone the right expression so that it doesn't get removed from the old ExpressionStatement,
					// which might be still in use by the definite assignment graph.
					VariableInitializer initializer = new VariableInitializer(v.Name, v.ReplacedAssignment.Right.Detach()).CopyAnnotationsFrom(v.ReplacedAssignment).WithAnnotation(v.ILVariable);
					VariableDeclarationStatement varDecl = new VariableDeclarationStatement {
						Type = (AstType)v.Type.Clone(),
						Variables = { initializer }
					};
					ExpressionStatement es = v.ReplacedAssignment.Parent as ExpressionStatement;
					if (es != null) {
						// Note: if this crashes with 'Cannot replace the root node', check whether two variables were assigned the same name
						es.ReplaceWith(varDecl.CopyAnnotationsFrom(es));
					} else {
						v.ReplacedAssignment.ReplaceWith(varDecl);
					}
				}
			}
			variablesToDeclare = null;
		}

		public void Run (RefactoringContext context)
		{
			var property = context.GetNode<PropertyDeclaration> ();
			
			string backingStoreName = context.GetNameProposal (property.Name);
			
			// create field
			var backingStore = new FieldDeclaration ();
			backingStore.ReturnType = property.ReturnType.Clone ();
			
			var initializer = new VariableInitializer (backingStoreName);
			backingStore.Variables.Add (initializer);
			
			// create new property & implement the get/set bodies
			var newProperty = (PropertyDeclaration)property.Clone ();
			var id1 = new IdentifierExpression (backingStoreName);
			var id2 = new IdentifierExpression (backingStoreName);
			newProperty.Getter.Body = new BlockStatement () {
				new ReturnStatement (id1)
			};
			newProperty.Setter.Body = new BlockStatement () {
				new ExpressionStatement (new AssignmentExpression (id2, AssignmentOperatorType.Assign, new IdentifierExpression ("value")))
			};
			
			using (var script = context.StartScript ()) {
				script.Replace (property, newProperty);
				script.InsertBefore (property, backingStore);
				script.Link (initializer, id1, id2);
			}
		}

            public override void VisitVariableInitializer(VariableInitializer variableInitializer)
            {
                base.VisitVariableInitializer (variableInitializer);

                // check if variable is assigned
                if (!variableInitializer.Initializer.IsNull)
                    return;
                var decl = variableInitializer.Parent as VariableDeclarationStatement;
                if (decl == null)
                    return;

                var resolveResult = ctx.Resolve (variableInitializer) as LocalResolveResult;
                if (resolveResult == null)
                    return;

                if (IsUsed (decl.Parent, resolveResult.Variable, variableInitializer))
                    return;

                AddIssue (variableInitializer.NameToken, ctx.TranslateString ("Remove unused local variable"),
                    script =>
                    {
                        if (decl.Variables.Count == 1) {
                            script.Remove (decl);
                        } else {
                            var newDeclaration = (VariableDeclarationStatement)decl.Clone ();
                            newDeclaration.Variables.Remove (
                                newDeclaration.Variables.FirstOrNullObject (v => v.Name == variableInitializer.Name));
                            script.Replace (decl, newDeclaration);
                        }
                    });
            }

			public override void VisitVariableInitializer (VariableInitializer variableInitializer)
			{
				base.VisitVariableInitializer (variableInitializer);

				if (!(ctx.Resolve (variableInitializer) is LocalResolveResult))
					return;
				if (HidesMember (ctx, variableInitializer, variableInitializer.Name))
					AddIssue (variableInitializer.NameToken,
						ctx.TranslateString ("Local variable has the same name as a member and hides it"));
			}

		bool ContainsGetter (PropertyDeclaration property, VariableInitializer initializer)
		{
			if (property.Getter.IsNull || property.Getter.Body.Statements.Count () != 1)
				return false;
			var ret = property.Getter.Body.Statements.Single () as ReturnStatement;
			if (ret == null)
				return false;
			return ret.Expression.IsMatch (new IdentifierExpression (initializer.Name)) || 
				ret.Expression.IsMatch (new MemberReferenceExpression (new ThisReferenceExpression (), initializer.Name));
		}

		public override IEnumerable<CodeAction> GetActions(RefactoringContext context)
		{
			var property = context.GetNode<PropertyDeclaration> ();
			if (property == null || !property.NameToken.Contains(context.Location))
				yield break;

			if (!IsNotImplemented (context, property.Getter.Body) ||
			    !IsNotImplemented (context, property.Setter.Body)) {
				yield break;
			}
			
			yield return new CodeAction(context.TranslateString("Implement property"), script => {
				string backingStoreName = context.GetNameProposal (property.Name);
				
				// create field
				var backingStore = new FieldDeclaration ();
				if (property.Modifiers.HasFlag (Modifiers.Static))
					backingStore.Modifiers |= Modifiers.Static;

				if (property.Setter.IsNull)
					backingStore.Modifiers |= Modifiers.Readonly;
				
				backingStore.ReturnType = property.ReturnType.Clone ();
				
				var initializer = new VariableInitializer (backingStoreName);
				backingStore.Variables.Add (initializer);
				
				// create new property & implement the get/set bodies
				var newProperty = (PropertyDeclaration)property.Clone ();
				Expression id1;
				if (backingStoreName == "value")
					id1 = new ThisReferenceExpression().Member("value");
				else
					id1 = new IdentifierExpression (backingStoreName);
				Expression id2 = id1.Clone();
				newProperty.Getter.Body = new BlockStatement () {
					new ReturnStatement (id1)
				};
				if (!property.Setter.IsNull) {
					newProperty.Setter.Body = new BlockStatement () {
						new AssignmentExpression (id2, AssignmentOperatorType.Assign, new IdentifierExpression ("value"))
					};
				}
				
				script.Replace (property, newProperty);
				script.InsertBefore (property, backingStore);
				if (!property.Setter.IsNull)
					script.Link (initializer, id1, id2);
				else
					script.Link (initializer, id1);
			}, property.NameToken);
		}

		public static MethodDeclaration CreateEventInvocator (RefactoringContext context, TypeDeclaration declaringType, EventDeclaration eventDeclaration, VariableInitializer initializer, IMethod invokeMethod, bool useExplictType)
		{
			bool hasSenderParam = false;
			IEnumerable<IParameter> pars = invokeMethod.Parameters;
			if (invokeMethod.Parameters.Any()) {
				var first = invokeMethod.Parameters [0];
				if (first.Name == "sender" /*&& first.Type == "System.Object"*/) {
					hasSenderParam = true;
					pars = invokeMethod.Parameters.Skip(1);
				}
			}
			const string handlerName = "handler";

			var arguments = new List<Expression>();
			if (hasSenderParam)
				arguments.Add(eventDeclaration.HasModifier (Modifiers.Static) ? (Expression)new PrimitiveExpression (null) : new ThisReferenceExpression());
			bool useThisMemberReference = false;
			foreach (var par in pars) {
				arguments.Add(new IdentifierExpression(par.Name));
				useThisMemberReference |= par.Name == initializer.Name;
			}
			var proposedHandlerName = GetNameProposal(initializer);
			var modifiers = eventDeclaration.HasModifier(Modifiers.Static) ? Modifiers.Static : Modifiers.Protected | Modifiers.Virtual;
			if (declaringType.HasModifier (Modifiers.Sealed)) {
				modifiers = Modifiers.None;
			}
			var methodDeclaration = new MethodDeclaration {
				Name = proposedHandlerName,
				ReturnType = new PrimitiveType ("void"),
				Modifiers = modifiers,
				Body = new BlockStatement {
					new VariableDeclarationStatement (
						useExplictType ? eventDeclaration.ReturnType.Clone () : new PrimitiveType ("var"), handlerName, 
						useThisMemberReference ? 
						(Expression)new MemberReferenceExpression (new ThisReferenceExpression (), initializer.Name) 
						: new IdentifierExpression (initializer.Name)
						),
					new IfElseStatement {
						Condition = new BinaryOperatorExpression (new IdentifierExpression (handlerName), BinaryOperatorType.InEquality, new PrimitiveExpression (null)),
						TrueStatement = new InvocationExpression (new IdentifierExpression (handlerName), arguments)
					}
				}
			};

			foreach (var par in pars) {
				var typeName = context.CreateShortType(par.Type);
				var decl = new ParameterDeclaration(typeName, par.Name);
				methodDeclaration.Parameters.Add(decl);
			}
			return methodDeclaration;
		}

		public IEnumerable<CodeAction> GetActions(RefactoringContext context)
		{
			var pexpr = context.GetNode<PrimitiveExpression>();
			if (pexpr == null)
				yield break;
			var statement = context.GetNode<Statement>();
			if (statement == null) {
				yield break;
			}

			var resolveResult = context.Resolve(pexpr);

			yield return new CodeAction(context.TranslateString("Create local constant"), script => {
				string name = CreateMethodDeclarationAction.CreateBaseName(pexpr, resolveResult.Type);
				var service = (NamingConventionService)context.GetService(typeof(NamingConventionService));
				if (service != null)
					name = service.CheckName(context, name, AffectedEntity.LocalConstant);

				var initializer = new VariableInitializer(name, pexpr.Clone());
				var decl = new VariableDeclarationStatement() {
					Type = context.CreateShortType(resolveResult.Type),
					Modifiers = Modifiers.Const,
					Variables = { initializer }
				};

				script.InsertBefore(statement, decl);
				var variableUsage = new IdentifierExpression(name);
				script.Replace(pexpr, variableUsage);
				script.Link(initializer.NameToken, variableUsage);
			});

			yield return new CodeAction(context.TranslateString("Create constant field"), script => {
				string name = CreateMethodDeclarationAction.CreateBaseName(pexpr, resolveResult.Type);
				var service = (NamingConventionService)context.GetService(typeof(NamingConventionService));
				if (service != null)
					name = service.CheckName(context, name, AffectedEntity.ConstantField);

				var initializer = new VariableInitializer(name, pexpr.Clone());

				var decl = new FieldDeclaration() {
					ReturnType = context.CreateShortType(resolveResult.Type),
					Modifiers = Modifiers.Const,
					Variables = { initializer }
				};

				var variableUsage = new IdentifierExpression(name);
				script.Replace(pexpr, variableUsage);
//				script.Link(initializer.NameToken, variableUsage);
				script.InsertWithCursor(context.TranslateString("Create constant"), Script.InsertPosition.Before, decl);
			});
		}

		public VariableInitializer ConvertToInitializer(VariableInitializer variableInitializer, ref IList<AstNode> statements)
		{
			if (variableInitializer == null)
				throw new ArgumentNullException("variableInitializer");
			if (statements == null)
				throw new ArgumentNullException("statements");

			Initialize(variableInitializer);
			accessPaths [mainAccessPath] = variableInitializer.Initializer.Clone();

			Convert(statements);
			statements = ReplacementNodeHelper.GetReplacedNodes(accessPaths [mainAccessPath]);
			return new VariableInitializer(mainAccessPath.RootName, accessPaths [mainAccessPath]);
		}

		static CodeAction MoveDeclarationAction(RefactoringContext context, AstNode insertAnchor,
		                                        VariableDeclarationStatement declarationStatement, VariableInitializer initializer)
		{
			var type = declarationStatement.Type.Clone();
			var name = initializer.Name;
			
			return new CodeAction(context.TranslateString("Move declaration to outer scope"), script =>  {
				script.InsertBefore(declarationStatement, new ExpressionStatement() {
					Expression = new AssignmentExpression(new IdentifierExpression(name), initializer.Initializer.Clone())
				});
				script.Remove(declarationStatement);
				script.InsertBefore(insertAnchor, new VariableDeclarationStatement(type, name, Expression.Null));
			});
		}

		static CodeAction MoveInitializerAction(RefactoringContext context, AstNode insertAnchor,
		                                        VariableDeclarationStatement declaration, VariableInitializer initializer)
		{
			var type = declaration.Type.Clone();
			var name = initializer.Name;
			return new CodeAction(context.TranslateString("Move initializer to outer scope"), script =>  {
				if (declaration.Variables.Count != 1) {
					var innerDeclaration = RemoveInitializer(declaration, initializer);
					script.InsertBefore(declaration, innerDeclaration);
				}
				script.Remove(declaration);
				var outerDeclaration = new VariableDeclarationStatement(type, name, initializer.Initializer.Clone());
				script.InsertBefore(insertAnchor, outerDeclaration);
			});
		}

		CodeAction HandleInitializer(RefactoringContext context, VariableInitializer initializer)
		{
			var objectCreateExpression = initializer.Initializer as ObjectCreateExpression;
			if (objectCreateExpression == null)
				return null;
			var initializerRR = context.Resolve(initializer) as LocalResolveResult;
			if (initializerRR == null)
				return null;
			IList<AstNode> statements = GetNodes(context.GetNode<Statement>());
			var converter = new StatementsToInitializerConverter(context);
			var newInitializer = converter.ConvertToInitializer(initializer, ref statements);
			if (statements.Count == 0)
				return null;
			return MakeAction(context, initializer, newInitializer, statements);
		}

			public override void VisitVariableInitializer (VariableInitializer variableInitializer)
			{
				base.VisitVariableInitializer (variableInitializer);

				var decl = variableInitializer.Parent as VariableDeclarationStatement;
				if (decl == null)
					return;

				var resolveResult = ctx.Resolve (variableInitializer) as LocalResolveResult;
				if (resolveResult == null)
					return;
				if (!TestOnlyAssigned (ctx, unit, resolveResult.Variable))
					return;
				AddIssue (variableInitializer.NameToken,
					ctx.TranslateString ("Local variable is assigned by its value is never used"));
			}