mcs/class/referencesource/System.Activities.Presentation/System.Activities.Presentation/System/Activities/Presentation/VisualBasicExpressionMorphHelper.cs

   1 //----------------------------------------------------------------
   2 // Copyright (c) Microsoft Corporation.  All rights reserved.
   3 //----------------------------------------------------------------
   4
   5 namespace System.Activities.Presentation
   6 {
   7     using System;
   8     using System.Activities.ExpressionParser;
   9     using System.Activities.Presentation.Expressions;
  10     using System.Activities.Presentation.View;
  11     using System.Runtime;
  12     using Microsoft.VisualBasic.Activities;
  13
  14     class VisualBasicExpressionMorphHelper : ExpressionMorphHelper
  15     {
  16         public override bool TryInferReturnType(ActivityWithResult expression, EditingContext context, out Type returnType)
  17         {
  18             bool succeeded = false;
  19             Fx.Assert(expression.GetType().GetGenericTypeDefinition() == typeof(VisualBasicValue<>) ||
  20                 expression.GetType().GetGenericTypeDefinition() == typeof(VisualBasicReference<>), "VisualBasicExpressionMorphHelper should only apply to VB expression.");
  21
  22             SourceExpressionException compileError;
  23             VisualBasicSettings settings;
  24             if (ExpressionHelper.IsGenericLocationExpressionType(expression))
  25             {
  26                 VisualBasicDesignerHelper.RecompileVisualBasicReference(
  27                         expression,
  28                         out returnType,
  29                         out compileError,
  30                         out settings);
  31             }
  32             else
  33             {
  34                 VisualBasicDesignerHelper.RecompileVisualBasicValue(
  35                      expression,
  36                      out returnType,
  37                      out compileError,
  38                      out settings);
  39             }
  40             if (compileError == null)
  41             {
  42                 succeeded = true;
  43                 if (settings != null)
  44                 {
  45                     //merge with import designer
  46                     foreach (VisualBasicImportReference reference in settings.ImportReferences)
  47                     {
  48                         ImportDesigner.AddImport(reference.Import, context);
  49                     }
  50                 }
  51             }
  52             return succeeded;
  53         }
  54
  55         public override bool TryMorphExpression(ActivityWithResult expression, bool isLocationExpression, Type newType,
  56             EditingContext context, out ActivityWithResult newExpression)
  57         {
  58             string expressionText = ExpressionHelper.GetExpressionString(expression);
  59             newExpression = VisualBasicEditor.CreateExpressionFromString(newType, expressionText, isLocationExpression, new ParserContext());
  60             return true;
  61         }
  62     }
  63 }