public override bool IsValid (RefactoringOptions options)
		{
			IResolver resolver = options.GetResolver ();
			INRefactoryASTProvider provider = options.GetASTProvider ();
			if (resolver == null || provider == null)
				return false;
			TextEditorData data = options.GetTextEditorData ();
			if (data == null)
				return false;
			ResolveResult resolveResult;
			if (data.IsSomethingSelected) {
				ExpressionResult expressionResult = new ExpressionResult (data.SelectedText.Trim ());
				if (expressionResult.Expression.Contains (" ") || expressionResult.Expression.Contains ("\t"))
					expressionResult.Expression = "(" + expressionResult.Expression + ")";
				resolveResult = resolver.Resolve (expressionResult, new DomLocation (data.Caret.Line, data.Caret.Column));
				if (resolveResult == null)
					return false;
				return true;
			}
			LineSegment lineSegment = data.Document.GetLine (data.Caret.Line);
			string line = data.Document.GetTextAt (lineSegment);
			Expression expression = provider.ParseExpression (line);
			BlockStatement block = provider.ParseText (line) as BlockStatement;
			if (expression == null || (block != null && block.Children[0] is LocalVariableDeclaration))
				return false;
			
			resolveResult = resolver.Resolve (new ExpressionResult (line), new DomLocation (options.Document.Editor.Caret.Line, options.Document.Editor.Caret.Column));
			return resolveResult.ResolvedType != null && !string.IsNullOrEmpty (resolveResult.ResolvedType.FullName) && resolveResult.ResolvedType.FullName != DomReturnType.Void.FullName;
		}

		public NRefactoryTemplateParameterDataProvider (TextEditorData editor, NRefactoryResolver resolver, IEnumerable<string> namespaces, ExpressionResult expressionResult, DomLocation loc)
		{
//			this.editor = editor;
			ResolveResult plainResolveResult = resolver.Resolve (expressionResult, loc);
			MethodResolveResult resolveResult = plainResolveResult as MethodResolveResult;
			if (resolveResult != null) {
				foreach (IMethod method in resolveResult.Methods) {
					if (method.TypeParameters.Count > 0)
						this.types.Add (method);
				}
			} else {
				string typeName = expressionResult.Expression.Trim ();
				foreach (string ns in namespaces) {
					string prefix = ns + (ns.Length > 0 ? "." : "") + typeName + "`";
					for (int i = 1; i < 99; i++) {
						IType possibleType = resolver.Dom.GetType (prefix + i);
						if (possibleType != null)
							this.types.Add (possibleType);
					}
				}
				IType resolvedType = plainResolveResult != null ? resolver.Dom.GetType (plainResolveResult.ResolvedType) : null;
				if (resolvedType == null) {
					int idx = expressionResult.Expression.LastIndexOf (".");
					if (idx < 0)
						return;
					typeName = expressionResult.Expression.Substring (idx + 1);
					expressionResult.Expression = expressionResult.Expression.Substring (0, idx);
					plainResolveResult = resolver.Resolve (expressionResult, loc);
					resolvedType = resolver.Dom.GetType (plainResolveResult.ResolvedType);
				}
				if (resolvedType == null)
					return;
				foreach (IType innerType in resolvedType.InnerTypes) {
					this.types.Add (innerType);
				}
			}
		}

		public bool IsInLinqContext (ExpressionResult result)
		{
			if (result.Contexts == null)
				return false;
			var ctx = (ExpressionContext.LinqContext)result.Contexts.FirstOrDefault (c => c is ExpressionContext.LinqContext);
			if (ctx == null)
				return false;
			int offset = this.textEditorData.Document.LocationToOffset (ctx.Line, ctx.Column);
			return !GetTextWithoutCommentsAndStrings (this.textEditorData.Document, offset, textEditorData.Caret.Offset).Any (p => p.Key == ';');
		}

		ICompletionDataList CreateCaseCompletionData (DomLocation location, ExpressionResult expressionResult)
		{
			NRefactoryResolver resolver = CreateResolver ();
			
			resolver.SetupResolver (location);
			
			SwitchFinder switchFinder = new SwitchFinder (location);
			if (resolver.MemberCompilationUnit != null)
				switchFinder.VisitCompilationUnit (resolver.MemberCompilationUnit, null);
			CompletionDataList result = new ProjectDomCompletionDataList ();
			if (switchFinder.SwitchStatement == null)
				return result;
			ResolveResult resolveResult = resolver.ResolveExpression (switchFinder.SwitchStatement.SwitchExpression, location);
			IType type = dom.GetType (resolveResult.ResolvedType);
			if (type != null && type.ClassType == ClassType.Enum) {
				OutputFlags flags = OutputFlags.None;
				var declaringType = resolver.CallingType;
				if (declaringType != null && dom != null) {
					foreach (IType t in new List<IType>(dom.GetInheritanceTree (declaringType))) {
						if (t.SearchMember (type.Name, true).Any (m => m.MemberType != MonoDevelop.Projects.Dom.MemberType.Type)) {
							flags |= OutputFlags.UseFullName;
							break;
						}
					}
				}
//				if (!foundType && (NamePrefix.Length == 0 || !type.Namespace.StartsWith (NamePrefix)) && !type.Namespace.EndsWith ("." + NamePrefix) && type.DeclaringType == null && NamePrefix != null && !NamePrefix.Contains ("::"))
//					flags |= OutputFlags.UseFullName;
				CompletionDataCollector cdc = new CompletionDataCollector (dom, result, Document.CompilationUnit, resolver.CallingType, location);
				cdc.Add (type, flags);
			}
			return result;
		}

		CompletionDataList CreateCtrlSpaceCompletionData (CodeCompletionContext ctx, ExpressionResult expressionResult)
		{
			NRefactoryResolver resolver = CreateResolver ();
			DomLocation cursorLocation = new DomLocation (ctx.TriggerLine, ctx.TriggerLineOffset);
			resolver.SetupResolver (cursorLocation);
			CompletionDataList result = new ProjectDomCompletionDataList ();
			CompletionDataCollector col = new CompletionDataCollector (dom, result, Document.CompilationUnit, resolver.CallingType, cursorLocation);
			
			if (expressionResult == null) {
				AddPrimitiveTypes (col);
				resolver.AddAccessibleCodeCompletionData (ExpressionContext.Global, col);
			} else if (expressionResult.ExpressionContext == ExpressionContext.TypeDeclaration) {
				AddPrimitiveTypes (col);
				AddNRefactoryKeywords (col, ICSharpCode.NRefactory.Parser.CSharp.Tokens.TypeLevel);
				resolver.AddAccessibleCodeCompletionData (expressionResult.ExpressionContext, col);
			} else if (expressionResult.ExpressionContext == ExpressionContext.InterfaceDeclaration) {
				AddPrimitiveTypes (col);
				AddNRefactoryKeywords (col, ICSharpCode.NRefactory.Parser.CSharp.Tokens.InterfaceLevel);
				resolver.AddAccessibleCodeCompletionData (expressionResult.ExpressionContext, col);
			} else if (expressionResult.ExpressionContext == ExpressionContext.MethodBody) {
				col.Add ("global", "md-keyword");
				col.Add ("var", "md-keyword");
				AddNRefactoryKeywords (col, ICSharpCode.NRefactory.Parser.CSharp.Tokens.StatementStart);
				AddPrimitiveTypes (col);
				resolver.AddAccessibleCodeCompletionData (expressionResult.ExpressionContext, col);
			} else if (expressionResult.ExpressionContext == ExpressionContext.InterfacePropertyDeclaration) {
				col.Add ("get", "md-keyword");
				col.Add ("set", "md-keyword");
			} else if (expressionResult.ExpressionContext == ExpressionContext.ConstraintsStart) {
				col.Add ("where", "md-keyword");
			} else if (expressionResult.ExpressionContext == ExpressionContext.Constraints) {
				col.Add ("new", "md-keyword");
				col.Add ("class", "md-keyword");
				col.Add ("struct", "md-keyword");
				AddPrimitiveTypes (col);
				resolver.AddAccessibleCodeCompletionData (expressionResult.ExpressionContext, col);
			} else if (expressionResult.ExpressionContext == ExpressionContext.Attribute) {
				col.Add ("assembly", "md-keyword");
				col.Add ("module", "md-keyword");
				col.Add ("type", "md-keyword");
				col.Add ("method", "md-keyword");
				col.Add ("field", "md-keyword");
				col.Add ("property", "md-keyword");
				col.Add ("event", "md-keyword");
				col.Add ("param", "md-keyword");
				col.Add ("return", "md-keyword");
				resolver.AddAccessibleCodeCompletionData (expressionResult.ExpressionContext, col);
			} else if (expressionResult.ExpressionContext == ExpressionContext.BaseConstructorCall) {
				col.Add ("this", "md-keyword");
				col.Add ("base", "md-keyword");
			} else if (expressionResult.ExpressionContext == ExpressionContext.ParameterType || expressionResult.ExpressionContext == ExpressionContext.FirstParameterType) {
				col.Add ("ref", "md-keyword");
				col.Add ("out", "md-keyword");
				col.Add ("params", "md-keyword");
				// C# 3.0 extension method
				if (expressionResult.ExpressionContext == ExpressionContext.FirstParameterType)
					col.Add ("this", "md-keyword");
				AddPrimitiveTypes (col);
				resolver.AddAccessibleCodeCompletionData (expressionResult.ExpressionContext, col);
			} else if (expressionResult.ExpressionContext == ExpressionContext.PropertyDeclaration) {
				AddNRefactoryKeywords (col, ICSharpCode.NRefactory.Parser.CSharp.Tokens.InPropertyDeclaration);
			} else if (expressionResult.ExpressionContext == ExpressionContext.EventDeclaration) {
				col.Add ("add", "md-keyword");
				col.Add ("remove", "md-keyword");
			} //else if (expressionResult.ExpressionContext == ExpressionContext.FullyQualifiedType) {} 
			else if (expressionResult.ExpressionContext == ExpressionContext.Default) {
				col.Add ("global", "md-keyword");
				col.Add ("var", "md-keyword");
				AddPrimitiveTypes (col);
				AddNRefactoryKeywords (col, ICSharpCode.NRefactory.Parser.CSharp.Tokens.ExpressionStart);
				AddNRefactoryKeywords (col, ICSharpCode.NRefactory.Parser.CSharp.Tokens.ExpressionContent);
				resolver.AddAccessibleCodeCompletionData (expressionResult.ExpressionContext, col);
			} else if (expressionResult.ExpressionContext == ExpressionContext.Global) {
				AddNRefactoryKeywords (col, ICSharpCode.NRefactory.Parser.CSharp.Tokens.GlobalLevel);
				CodeTemplateService.AddCompletionDataForMime ("text/x-csharp", result);
			} else if (expressionResult.ExpressionContext == ExpressionContext.ObjectInitializer) {
				ExpressionContext exactContext = new NewCSharpExpressionFinder (dom).FindExactContextForObjectInitializer (textEditorData, resolver.Unit, Document.FileName, resolver.CallingType);
				if (exactContext is ExpressionContext.TypeExpressionContext) {
					IReturnType objectInitializer = ((ExpressionContext.TypeExpressionContext)exactContext).UnresolvedType;
					if (objectInitializer.ArrayDimensions > 0 || objectInitializer.PointerNestingLevel > 0) {
						col.Add ("global", "md-keyword");
						col.Add ("new", "md-keyword");
						AddPrimitiveTypes (col);
						resolver.AddAccessibleCodeCompletionData (expressionResult.ExpressionContext, col);
						return result;
					}
						
					IType foundType = resolver.SearchType (objectInitializer);
					if (foundType == null)
						foundType = dom.GetType (objectInitializer);
					
					if (foundType != null) {
						bool includeProtected = DomType.IncludeProtected (dom, foundType, resolver.CallingType);
						foreach (IType type in dom.GetInheritanceTree (foundType)) {
							foreach (IProperty property in type.Properties) {
								if (property.IsAccessibleFrom (dom, resolver.CallingType, resolver.CallingMember, includeProtected)) {
									col.Add (property);
								}
							}
							foreach (var field in type.Fields) {
//.........这里部分代码省略.........

		ICompletionDataList CreateCompletionData (DomLocation location, ResolveResult resolveResult, 
		                                          ExpressionResult expressionResult, NRefactoryResolver resolver)
		{
			if (resolveResult == null || expressionResult == null || dom == null)
				return null;
			CompletionDataList result = new ProjectDomCompletionDataList ();
			IEnumerable<object> objects = resolveResult.CreateResolveResult (dom, resolver != null ? resolver.CallingMember : null);
			CompletionDataCollector col = new CompletionDataCollector (dom, result, Document.CompilationUnit, resolver != null ? resolver.CallingType : null, location);
			col.HideExtensionParameter = !resolveResult.StaticResolve;
			col.NamePrefix = expressionResult.Expression;
			bool showOnlyTypes = expressionResult.Contexts.Any (ctx => ctx == ExpressionContext.InheritableType || ctx == ExpressionContext.Constraints);
			if (objects != null) {
				foreach (object obj in objects) {
					if (expressionResult.ExpressionContext != null && expressionResult.ExpressionContext.FilterEntry (obj))
						continue;
					if (expressionResult.ExpressionContext == ExpressionContext.NamespaceNameExcepted && !(obj is Namespace))
						continue;
					if (showOnlyTypes && !(obj is IType))
						continue;
					CompletionData data = col.Add (obj);
					if (data != null && expressionResult.ExpressionContext == ExpressionContext.Attribute && data.CompletionText != null && data.CompletionText.EndsWith ("Attribute")) {
						string newText = data.CompletionText.Substring (0, data.CompletionText.Length - "Attribute".Length);
						data.SetText (newText);
					}
				}
			}
			
			return result;
		}

		ICompletionDataList CreateCaseCompletionData (DomLocation location, ExpressionResult expressionResult)
		{
			NRefactoryResolver resolver = CreateResolver ();
			
			resolver.SetupResolver (location);
			
			SwitchFinder switchFinder = new SwitchFinder (location);
			if (resolver.MemberCompilationUnit != null)
				switchFinder.VisitCompilationUnit (resolver.MemberCompilationUnit, null);
			CompletionDataList result = new ProjectDomCompletionDataList ();
			if (switchFinder.SwitchStatement == null)
				return result;
			ResolveResult resolveResult = resolver.ResolveExpression (switchFinder.SwitchStatement.SwitchExpression, location);
			IType type = dom.GetType (resolveResult.ResolvedType);
			if (type != null && type.ClassType == ClassType.Enum) {
				CompletionDataCollector cdc = new CompletionDataCollector (dom, result, Document.CompilationUnit, resolver.CallingType, location);
				cdc.Add (type);
			}
			return result;
		}

		internal static RefactoringOptions CreateRefactoringOptions (string text)
		{
			int cursorPosition = -1;
			int endPos = text.IndexOf ('$');
			if (endPos >= 0) {
				cursorPosition = endPos;
				text = text.Substring (0, cursorPosition) + text.Substring (cursorPosition + 1);
			}
			
			int selectionStart = -1;
			int selectionEnd   = -1;
			int idx = text.IndexOf ("<-");
			if (idx >= 0) {
				selectionStart = idx;
				text = text.Substring (0, idx) + text.Substring (idx + 2);
				selectionEnd = idx = text.IndexOf ("->");
				
				text = text.Substring (0, idx) + text.Substring (idx + 2);
				if (cursorPosition < 0)
					cursorPosition = selectionEnd - 1;
			}
			
			TestWorkbenchWindow tww = new TestWorkbenchWindow ();
			TestViewContent sev = new TestViewContent ();
	//		return new RefactoringOptions ();
			
			DotNetProject project = new DotNetAssemblyProject ("C#");
			Solution solution = new Solution ();
			solution.RootFolder.Items.Add (project);
			project.FileName = GetTempFile (".csproj");
			string file = GetTempFile (".cs");
			project.AddFile (file);
			string parsedText = text;
			string editorText = text;
			ProjectDomService.Load (project);
			ProjectDom dom = ProjectDomService.GetProjectDom (project);
			dom.ForceUpdate (true);
			ProjectDomService.Parse (project, file, delegate { return parsedText; });
			ProjectDomService.Parse (project, file, delegate { return parsedText; });
			
			sev.Project = project;
			sev.ContentName = file;
			sev.Text = editorText;
			sev.CursorPosition = cursorPosition;
			
			tww.ViewContent = sev;
			var doc = new MonoDevelop.Ide.Gui.Document (tww);
			doc.Editor.Document.MimeType = "text/x-csharp";
			doc.Editor.Document.FileName = file;
			doc.ParsedDocument = new McsParser ().Parse (null, sev.ContentName, parsedText);
			foreach (var e in doc.ParsedDocument.Errors)
				Console.WriteLine (e);
			if (cursorPosition >= 0)
				doc.Editor.Caret.Offset = cursorPosition;
			if (selectionStart >= 0) 
				doc.Editor.SetSelection (selectionStart, selectionEnd);
			
			NRefactoryResolver resolver = new NRefactoryResolver (dom, 
			                                                      doc.ParsedDocument.CompilationUnit, 
			                                                      sev.Data, 
			                                                      file);
			
			ExpressionResult expressionResult;
			if (selectionStart >= 0) {
				expressionResult = new ExpressionResult (editorText.Substring (selectionStart, selectionEnd - selectionStart).Trim ());
				endPos = selectionEnd;
			} else {
				expressionResult = new NewCSharpExpressionFinder (dom).FindFullExpression (doc.Editor, cursorPosition + 1);
			}
			ResolveResult resolveResult = endPos >= 0 ? resolver.Resolve (expressionResult, new DomLocation (doc.Editor.Caret.Line, doc.Editor.Caret.Column)) : null;
			
			RefactoringOptions result = new RefactoringOptions {
				Document = doc,
				Dom = dom,
				ResolveResult = resolveResult,
				SelectedItem = null
			};
			if (resolveResult is MemberResolveResult)
				result.SelectedItem = ((MemberResolveResult)resolveResult).ResolvedMember;
			if (resolveResult is LocalVariableResolveResult)
				result.SelectedItem = ((LocalVariableResolveResult)resolveResult).LocalVariable;
			if (resolveResult is ParameterResolveResult)
				result.SelectedItem = ((ParameterResolveResult)resolveResult).Parameter;
			result.TestFileProvider = new FileProvider (result);
			return result;
		}

		public MonoDevelop.Projects.Dom.ResolveResult GetLanguageItem (ProjectDom dom, Mono.TextEditor.TextEditorData data, int offset, string expression)
		{
			string fileName = data.Document.FileName;
			MonoDevelop.Ide.Gui.Document doc = IdeApp.Workbench.ActiveDocument;
			if (doc == null)
				return null;
			
			IParser parser = ProjectDomService.GetParser (fileName, data.Document.MimeType);
			if (parser == null)
				return null;
			
			IResolver         resolver = parser.CreateResolver (dom, doc, fileName);
			IExpressionFinder expressionFinder = parser.CreateExpressionFinder (dom);
			if (resolver == null || expressionFinder == null) 
				return null;
			string txt = data.Document.Text;
			int wordEnd = offset;
			while (wordEnd < txt.Length && (Char.IsLetterOrDigit (txt[wordEnd]) || txt[wordEnd] == '_'))
				wordEnd++;
			ExpressionResult expressionResult = new ExpressionResult (expression);
			expressionResult.ExpressionContext = ExpressionContext.MethodBody;
			
			DocumentLocation loc = data.Document.OffsetToLocation (offset);
			string savedExpression = null;
			ResolveResult resolveResult;
			
			if (expressionResult.ExpressionContext == ExpressionContext.Attribute) {
				savedExpression = expressionResult.Expression;
				expressionResult.Expression += "Attribute";
				expressionResult.ExpressionContext = ExpressionContext.ObjectCreation;
			} 
			resolveResult = resolver.Resolve (expressionResult, new DomLocation (loc.Line + 1, loc.Column + 1));
			if (savedExpression != null && resolveResult == null) {
				expressionResult.Expression = savedExpression;
				resolveResult = resolver.Resolve (expressionResult, new DomLocation (loc.Line + 1, loc.Column + 1));
			}
			// Search for possible generic parameters.
//			if (this.resolveResult == null || this.resolveResult.ResolvedType == null || String.IsNullOrEmpty (this.resolveResult.ResolvedType.Name)) {
				int j = data.Document.LocationToOffset (expressionResult.Region.End.Line - 1, expressionResult.Region.End.Column - 1);
				int bracket = 0;
				for (int i = j; i >= 0 && i < data.Document.Length; i++) {
					char ch = data.Document.GetCharAt (i);
					if (Char.IsWhiteSpace (ch))
						continue;
					if (ch == '<') {
						bracket++;
					} else if (ch == '>') {
						bracket--;
						if (bracket == 0) {
							expressionResult.Expression += data.Document.GetTextBetween (j, i + 1);
							expressionResult.ExpressionContext = ExpressionContext.ObjectCreation;
							resolveResult = resolver.Resolve (expressionResult, new DomLocation (loc.Line + 1, loc.Column + 1));
							break;
						}
					} else {
						if (bracket == 0)
							break;
					}
				}
//			}
			
			// To resolve method overloads the full expression must be parsed.
			// ex.: Overload (1)/ Overload("one") - parsing "Overload" gives just a MethodResolveResult
			if (resolveResult is MethodResolveResult) 
				resolveResult = resolver.Resolve (expressionFinder.FindFullExpression (txt, wordEnd), new DomLocation (loc.Line + 1, loc.Column + 1)) ?? resolveResult;
			return resolveResult;
		}

		ResolveResult IResolver.Resolve (ExpressionResult expressionResult, DomLocation resolvePosition)
		{
			var expr = expressionResult as PythonExpressionResult;
			if (expr == null)
				return null;
			
			var doc = ProjectDomService.GetParsedDocument (m_dom, m_filename) as PythonParsedDocument;
			if (doc == null)
				return null;
			
			var unit = doc.CompilationUnit as PythonCompilationUnit;
			if (unit == null)
				return null;
			
			if (expr.Type == "def")
			{
				var type = unit.GetTypeAt (resolvePosition);
				if (type != null)
				{
					// resolving a method
					foreach (var func in type.Methods)
					{
						if (func.Name == expr.Word)
						{
							var l = new List<IMember> ();
							l.Add (func);
							return new MethodResolveResult (l);
						}
					}
				}
			}
			
			else if (expr.Type == "class")
			{
				var type = unit.GetTypeAt (resolvePosition);
				if (type != null && type.Name == expr.Word)
					return new MemberResolveResult (type);
			}
			
			else if (expr.Word == "self")
			{
				var type = unit.GetTypeAt (resolvePosition);
				if (type != null)
					return new MemberResolveResult (type);
			}
			
			else if (expr.Type == "self")
			{
				// looking for a member of self
				var type = unit.GetTypeAt (resolvePosition);
				if (type != null)
				{
					foreach (var attr in type.Fields)
					{
						if (attr.Name == expr.Word)
							return new MemberResolveResult (attr);
					}
					
					foreach (var method in type.Methods)
					{
						if (method.Name == expr.Word)
							return CreateMethodResult (method);
					}
				}
			}
			
			return null;
		}

 Expression ParseExpression(ExpressionResult expressionResult)
 {
     if (expressionResult == null || String.IsNullOrEmpty (expressionResult.Expression))
         return null;
     string expr = expressionResult.Expression.Trim ();
     if (!expr.EndsWith (";"))
         expr += ";";
     using (ICSharpCode.NRefactory.IParser parser = ICSharpCode.NRefactory.ParserFactory.CreateParser (this.lang, new StringReader (expr))) {
         Expression result = parser.ParseExpression();
         if (result is BinaryOperatorExpression) {
             TypeReference typeRef = ParseTypeReference (expressionResult);
             if (typeRef != null) {
                 return new TypeReferenceExpression (typeRef);
             }
         }
         return result;
     }
 }

 static TypeReference ParseTypeReference(ExpressionResult expressionResult)
 {
     if (expressionResult == null || String.IsNullOrEmpty (expressionResult.Expression))
         return null;
     string expr = expressionResult.Expression.Trim ();
     using (ICSharpCode.NRefactory.IParser parser = ICSharpCode.NRefactory.ParserFactory.CreateParser (SupportedLanguage.CSharp, new StringReader ("typeof(" + expr + ");"))) {
         TypeOfExpression typeOfExpression = parser.ParseExpression () as TypeOfExpression;
         if (typeOfExpression != null)
             return typeOfExpression.TypeReference;
     }
     return null;
 }

        public ResolveResult Resolve(ExpressionResult expressionResult, DomLocation resolvePosition)
        {
            this.SetupResolver (resolvePosition);
            ResolveVisitor visitor = new ResolveVisitor (this);
            ResolveResult result;
            //			System.Console.WriteLine("expressionResult:" + expressionResult);

            if (unit != null && expressionResult.ExpressionContext == ExpressionContext.AttributeArguments) {
                string attributeName = NewFSharpExpressionFinder.FindAttributeName (editor, unit, unit.FileName);
                if (attributeName != null) {
                    IType type = dom.SearchType (new SearchTypeRequest (unit, new DomReturnType (attributeName + "Attribute"), CallingType));
                    if (type == null)
                        type = dom.SearchType (new SearchTypeRequest (unit, new DomReturnType (attributeName), CallingType));
                    if (type != null) {
                        foreach (IProperty property in type.Properties) {
                            if (property.Name == expressionResult.Expression) {
                                return new MemberResolveResult (property);
                            }
                        }
                    }
                }
            }

            TypeReference typeRef;
            if (expressionResult != null && expressionResult.ExpressionContext != null && expressionResult.ExpressionContext.IsObjectCreation) {
                typeRef = ParseTypeReference (expressionResult);
                if (typeRef != null) {
                    if (dom.NamespaceExists (typeRef.Type)) {
            //						System.Console.WriteLine("namespace resolve result");
                        result = new NamespaceResolveResult (typeRef.Type);
                    } else {
                        result = visitor.CreateResult (ConvertTypeReference (typeRef));
                    }
            //					System.Console.WriteLine("type reference resolve result");
                    result.ResolvedExpression = expressionResult;
                    if (dom.GetType (result.ResolvedType) != null)
                        return result;
                }
            }
            expr = ParseExpression (expressionResult);

            //			System.Console.WriteLine("parsed expression:" + expr);
            if (expr == null) {
            //				System.Console.WriteLine("Can't parse expression");
                return null;
            }

            result = visitor.Resolve (expr);
            //			if (CallingMember == null && result != null)
            //				result.StaticResolve = true;
            //			System.Console.WriteLine("result:" + result + "STATIC" + result.StaticResolve);
            result.ResolvedExpression = expressionResult;
            return result;
        }

 public static IReturnType ParseReturnType(ExpressionResult expressionResult)
 {
     TypeReference typeReference = ParseTypeReference (expressionResult);
     if (typeReference == null)
         return null;
     return ConvertTypeReference (typeReference);
 }

		public ICompletionDataList HandleKeywordCompletion (CodeCompletionContext completionContext, ExpressionResult result, int wordStart, string word)
		{
			if (stateTracker.Engine.IsInsideDocLineComment || stateTracker.Engine.IsInsideOrdinaryCommentOrString)
				return null;
			DomLocation location = new DomLocation (completionContext.TriggerLine, completionContext.TriggerLineOffset);
			switch (word) {
			case "using":
				if (result.ExpressionContext != ExpressionContext.NamespaceNameExcepted)
					return null;
				return CreateCompletionData (location, new NamespaceResolveResult (""), result, null);
			case "namespace":
				result.ExpressionContext = ExpressionContext.NamespaceNameExcepted;
				return CreateCompletionData (location, new NamespaceResolveResult (""), result, null);
			case "case":
				return CreateCaseCompletionData (location, result);
			case ",":
			case ":":
				if (result.ExpressionContext == ExpressionContext.InheritableType) {
					IType cls = NRefactoryResolver.GetTypeAtCursor (Document.CompilationUnit, Document.FileName, new DomLocation (completionContext.TriggerLine, completionContext.TriggerLineOffset));
					CompletionDataList completionList = new ProjectDomCompletionDataList ();
					List<string> namespaceList = GetUsedNamespaces ();
					CSharpTextEditorCompletion.CompletionDataCollector col = new CSharpTextEditorCompletion.CompletionDataCollector (dom, completionList, Document.CompilationUnit, null, location);
					bool isInterface = false;
					HashSet<string> baseTypeNames = new HashSet<string> ();
					if (cls != null) {
						baseTypeNames.Add (cls.Name);
						if (cls.ClassType == ClassType.Struct)
							isInterface = true;
					}
					int tokenIndex = completionContext.TriggerOffset;

										// Search base types " : [Type1, ... ,TypeN,] <Caret>"
					string token = null;
					do {
						token = GetPreviousToken (ref tokenIndex, false);
						if (string.IsNullOrEmpty (token))
							break;
						token = token.Trim ();
						if (Char.IsLetterOrDigit (token[0]) || token[0] == '_') {
							IType baseType = dom.SearchType (Document.CompilationUnit, Document.CompilationUnit, token);
							if (baseType != null) {
								if (baseType.ClassType != ClassType.Interface)
									isInterface = true;
								baseTypeNames.Add (baseType.Name);
							}
						}
					} while (token != ":");
					foreach (object o in dom.GetNamespaceContents (namespaceList, true, true)) {
						IType type = o as IType;
						if (type != null && (type.IsStatic || type.IsSealed || baseTypeNames.Contains (type.Name) || isInterface && type.ClassType != ClassType.Interface)) {
							continue;
						}
						if (o is Namespace && !namespaceList.Any (ns => ns.StartsWith (((Namespace)o).FullName)))
							continue;
						col.Add (o);
					}
					// Add inner classes
					Stack<IType> innerStack = new Stack<IType> ();
					innerStack.Push (cls);
					while (innerStack.Count > 0) {
						IType curType = innerStack.Pop ();
						if (curType == null)
							continue;
						foreach (IType innerType in curType.InnerTypes) {
							if (innerType != cls)
								// don't add the calling class as possible base type
								col.Add (innerType);
						}
						if (curType.DeclaringType != null)
							innerStack.Push (curType.DeclaringType);
					}
					return completionList;
				}
				break;
			case "is":
			case "as":
				
				{
					CompletionDataList completionList = new ProjectDomCompletionDataList ();
					ExpressionResult expressionResult = FindExpression (dom, completionContext, wordStart - textEditorData.Caret.Offset);
					NRefactoryResolver resolver = CreateResolver ();
					ResolveResult resolveResult = resolver.Resolve (expressionResult, new DomLocation (completionContext.TriggerLine, completionContext.TriggerLineOffset));
					if (resolveResult != null && resolveResult.ResolvedType != null) {
						CompletionDataCollector col = new CompletionDataCollector (dom, completionList, Document.CompilationUnit, resolver.CallingType, location);
						IType foundType = null;
						if (word == "as") {
							ExpressionContext exactContext = new NewCSharpExpressionFinder (dom).FindExactContextForAsCompletion (textEditorData, Document.CompilationUnit, Document.FileName, resolver.CallingType);
							if (exactContext is ExpressionContext.TypeExpressionContext) {
								foundType = resolver.SearchType (((ExpressionContext.TypeExpressionContext)exactContext).Type);
								AddAsCompletionData (col, foundType);
							}
						}
					
						if (foundType == null)
							foundType = resolver.SearchType (resolveResult.ResolvedType);
					
						if (foundType != null) {
							if (foundType.ClassType == ClassType.Interface)
								foundType = resolver.SearchType (DomReturnType.Object);
						
//.........这里部分代码省略.........

		public override List<Change> PerformChanges (RefactoringOptions options, object prop)
		{
			varCount = 0;
			selectionStart = selectionEnd = -1;
			List<Change> result = new List<Change> ();
			IResolver resolver = options.GetResolver ();
			INRefactoryASTProvider provider = options.GetASTProvider ();
			if (resolver == null || provider == null)
				return result;
			TextEditorData data = options.GetTextEditorData ();
			if (data == null)
				return result;
			ResolveResult resolveResult;
			LineSegment lineSegment;
			ICSharpCode.NRefactory.Ast.CompilationUnit unit = provider.ParseFile (data.Document.Text);
			MonoDevelop.Refactoring.ExtractMethod.VariableLookupVisitor visitor = new MonoDevelop.Refactoring.ExtractMethod.VariableLookupVisitor (resolver, new DomLocation (data.Caret.Line, data.Caret.Column));
			if (options.ResolveResult == null) {
				LoggingService.LogError ("resolve result == null:" + options.ResolveResult);
				return result;
			}
			IMember callingMember = options.ResolveResult.CallingMember;
			if (callingMember != null)
				visitor.MemberLocation = new Location (callingMember.Location.Column, callingMember.Location.Line);
			unit.AcceptVisitor (visitor, null);
			
			if (data.IsSomethingSelected) {
				ExpressionResult expressionResult = new ExpressionResult (data.SelectedText.Trim ());
				if (expressionResult.Expression.Contains (" ") || expressionResult.Expression.Contains ("\t"))
					expressionResult.Expression = "(" + expressionResult.Expression + ")";
				resolveResult = resolver.Resolve (expressionResult, new DomLocation (data.Caret.Line, data.Caret.Column));
				if (resolveResult == null)
					return result;
				IReturnType resolvedType = resolveResult.ResolvedType;
				if (resolvedType == null || string.IsNullOrEmpty (resolvedType.Name))
					resolvedType = DomReturnType.Object;
				varName = CreateVariableName (resolvedType, visitor);
				TypeReference returnType;
				if (resolveResult.ResolvedType == null || string.IsNullOrEmpty (resolveResult.ResolvedType.Name)) {
					returnType = new TypeReference ("var");
					returnType.IsKeyword = true;
				} else {
					returnType = options.ShortenTypeName (resolveResult.ResolvedType).ConvertToTypeReference ();
				}
				options.ParseMember (resolveResult.CallingMember);
				
				TextReplaceChange insert = new TextReplaceChange ();
				insert.FileName = options.Document.FileName;
				insert.Description = GettextCatalog.GetString ("Insert variable declaration");
				
				LocalVariableDeclaration varDecl = new LocalVariableDeclaration (returnType);
				varDecl.Variables.Add (new VariableDeclaration (varName, provider.ParseExpression (data.SelectedText)));
				
				GetContainingEmbeddedStatementVisitor blockVisitor = new GetContainingEmbeddedStatementVisitor ();
				blockVisitor.LookupLocation = new Location (data.Caret.Column, data.Caret.Line );
			
				unit.AcceptVisitor (blockVisitor, null);
				
				StatementWithEmbeddedStatement containing = blockVisitor.ContainingStatement as StatementWithEmbeddedStatement;
				
				if (containing != null && !(containing.EmbeddedStatement is BlockStatement)) {
					insert.Offset = data.Document.LocationToOffset (containing.StartLocation.Line, containing.StartLocation.Column);
					lineSegment = data.Document.GetLineByOffset (insert.Offset);
					insert.RemovedChars = data.Document.LocationToOffset (containing.EndLocation.Line, containing.EndLocation.Column) - insert.Offset;
					BlockStatement insertedBlock = new BlockStatement ();
					insertedBlock.AddChild (varDecl);
					insertedBlock.AddChild (containing.EmbeddedStatement);
					
					containing.EmbeddedStatement = insertedBlock;
					insert.InsertedText = provider.OutputNode (options.Dom, containing, options.GetWhitespaces (lineSegment.Offset)).TrimStart ();
					int offset, length;
					if (SearchSubExpression (insert.InsertedText, data.SelectedText, 0, out offset, out length)) 
					if (SearchSubExpression (insert.InsertedText, data.SelectedText, offset + 1, out offset, out length)) {
						insert.InsertedText = insert.InsertedText.Substring (0, offset) + varName + insert.InsertedText.Substring (offset + length);
						insertOffset = insert.Offset + offset;
					}
					
				} else if (blockVisitor.ContainingStatement is IfElseStatement) {
					IfElseStatement ifElse = blockVisitor.ContainingStatement as IfElseStatement;
					
					insert.Offset = data.Document.LocationToOffset (blockVisitor.ContainingStatement.StartLocation.Line, blockVisitor.ContainingStatement.StartLocation.Column);
					lineSegment = data.Document.GetLineByOffset (insert.Offset);
					insert.RemovedChars = data.Document.LocationToOffset (blockVisitor.ContainingStatement.EndLocation.Line, blockVisitor.ContainingStatement.EndLocation.Column) - insert.Offset;
					BlockStatement insertedBlock = new BlockStatement ();
					insertedBlock.AddChild (varDecl);
					if (blockVisitor.ContainsLocation (ifElse.TrueStatement[0])) {
						insertedBlock.AddChild (ifElse.TrueStatement[0]);
						ifElse.TrueStatement[0] = insertedBlock;
					} else {
						insertedBlock.AddChild (ifElse.FalseStatement[0]);
						ifElse.FalseStatement[0] = insertedBlock;
					}
					
					insert.InsertedText = provider.OutputNode (options.Dom, blockVisitor.ContainingStatement, options.GetWhitespaces (lineSegment.Offset));
					int offset, length;
					
					if (SearchSubExpression (insert.InsertedText, provider.OutputNode (options.Dom, insertedBlock), 0, out offset, out length)) 
					if (SearchSubExpression (insert.InsertedText, data.SelectedText, offset + 1, out offset, out length)) 
					if (SearchSubExpression (insert.InsertedText, data.SelectedText, offset + 1, out offset, out length)) {
						insert.InsertedText = insert.InsertedText.Substring (0, offset) + varName + insert.InsertedText.Substring (offset + length);
						insertOffset = insert.Offset + offset;
//.........这里部分代码省略.........

		public override object VisitIdentifierExpression (ICSharpCode.NRefactory.Ast.IdentifierExpression identifierExpression, object data)
		{
			if (!variables.ContainsKey (identifierExpression.Identifier)) {

				ExpressionResult expressionResult = new ExpressionResult (identifierExpression.Identifier);

				ResolveResult result = resolver.Resolve (expressionResult, position);
				
				MemberResolveResult mrr = result as MemberResolveResult;
				ReferencesMember |= mrr != null && mrr.ResolvedMember != null && !mrr.ResolvedMember.IsStatic;
				
				if (!(result is LocalVariableResolveResult || result is ParameterResolveResult))
					return base.VisitIdentifierExpression (identifierExpression, data);
				
				// result.ResolvedType == null may be true for namespace names or undeclared variables
				if (!result.StaticResolve && !variables.ContainsKey (identifierExpression.Identifier)) {
					variables[identifierExpression.Identifier] = new VariableDescriptor (identifierExpression.Identifier) {
						InitialValueUsed = !valueGetsChanged,
						Location = new DocumentLocation (MemberLocation.Line + identifierExpression.StartLocation.Line, identifierExpression.StartLocation.Column)

					};
					variables[identifierExpression.Identifier].ReturnType = result.ResolvedType;
				}
				if (result != null && !result.StaticResolve && result.ResolvedType != null && !(result is MethodResolveResult) && !(result is NamespaceResolveResult) && !(result is MemberResolveResult))