C# CodeWriter.GetNewExpression方法代码示例

        public override void WriteClassHeader(CodeWriter writer, DbLinq.Schema.Dbml.Table table, GenerationContext context)
        {
            using (writer.WriteRegion(string.Format("{0} handling", typeof(INotifyPropertyChanging).Name)))
            {
                const string eventName = "PropertyChanging"; // do not change, part of INotifyPropertyChanging
                const string emptyArgs = "emptyChangingEventArgs";

                // event
                writer.WriteEvent(SpecificationDefinition.Public, eventName, typeof(PropertyChangingEventHandler).Name);
                writer.WriteLine();
                // empty event arg
                writer.WriteField(SpecificationDefinition.Private | SpecificationDefinition.Static,
                                  writer.GetAssignmentExpression(emptyArgs, writer.GetNewExpression(
                                                                                writer.GetMethodCallExpression(typeof(PropertyChangingEventArgs).Name, "\"\""))),
                                  typeof(PropertyChangingEventArgs).Name);
                // method
                using (writer.WriteMethod(SpecificationDefinition.Protected | SpecificationDefinition.Virtual,
                                          sendPropertyChangingMethod, null))
                {
                    using (writer.WriteIf(writer.GetDifferentExpression(eventName, writer.GetNullExpression())))
                    {
                        writer.WriteLine(writer.GetStatement(writer.GetMethodCallExpression(eventName,
                                                                                            writer.GetThisExpression(), emptyArgs)));
                    }
                }
            }
        }

 protected virtual void WriteDataContextCtors(CodeWriter writer, Database schema, Type contextBaseType, GenerationContext context)
 {
     // ctor taking a connections tring
     WriteDataContextCtor(writer, schema, contextBaseType,
            new[] { new ParameterDefinition { Name = "connectionString", Type = typeof(string) } },
            new[] { "connectionString" },
            new[] { typeof(string) },
            context);
     // the two constructors below have the same prototype, so they are mutually exclusive
     // the base class requires a IVendor
     if (!WriteDataContextCtor(writer, schema, contextBaseType,
                          new[] { new ParameterDefinition { Name = "connection", Type = typeof(IDbConnection) } },
                          new[] { "connection", writer.GetNewExpression(writer.GetMethodCallExpression(writer.GetLiteralFullType(context.SchemaLoader.Vendor.GetType()))) },
                          new[] { typeof(IDbConnection), typeof(IVendor) },
                          context))
     {
         // OR the base class requires no IVendor
         WriteDataContextCtor(writer, schema, contextBaseType,
                              new[] { new ParameterDefinition { Name = "connection", Type = typeof(IDbConnection) } },
                              new[] { "connection" },
                              new[] { typeof(IDbConnection) },
                              context);
     }
     // ctor(string, MappingSource)
     WriteDataContextCtor(writer, schema, contextBaseType,
            new[] {
                new ParameterDefinition { Name = "connection", Type = typeof(string) },
                new ParameterDefinition { Name = "mappingSource", Type = typeof(MappingSource) },
            },
            new[] { "connection", "mappingSource" },
            new[] { typeof(string), typeof (MappingSource) },
            context);
     // ctor(IDbConnection, MappingSource)
     WriteDataContextCtor(writer, schema, contextBaseType,
             new[] {
                 new ParameterDefinition { Name = "connection", Type = typeof(IDbConnection) },
                 new ParameterDefinition { Name = "mappingSource", Type = typeof(MappingSource) },
             },
             new[] { "connection", "mappingSource" },
             new[] { typeof(IDbConnection), typeof(MappingSource) },
             context);
     // just in case you'd like to specify another vendor than the one who helped generating this file
     WriteDataContextCtor(writer, schema, contextBaseType,
             new[] {
                 new ParameterDefinition { Name = "connection", Type = typeof(IDbConnection) },
                 new ParameterDefinition { Name = "vendor", Type = typeof(IVendor) },
             },
             new[] { "connection", "vendor" },
             new[] { typeof(IDbConnection), typeof(IVendor) },
             context);
     WriteDataContextCtor(writer, schema, contextBaseType,
             new[] {
                 new ParameterDefinition { Name = "connection", Type = typeof(IDbConnection) },
                 new ParameterDefinition { Name = "mappingSource", Type = typeof(MappingSource) },
                 new ParameterDefinition { Name = "vendor", Type = typeof(IVendor) },
             },
             new[] { "connection", "mappingSource", "vendor" },
             new[] { typeof(IDbConnection), typeof(MappingSource), typeof(IVendor) },
             context);
 }

        public override void WriteClassHeader(CodeWriter writer, DbLinq.Schema.Dbml.Table table, GenerationContext context)
        {
            using (writer.WriteRegion(string.Format("{0} handling", typeof(INotifyPropertyChanged).Name)))
            {
                const string eventName = "PropertyChanged"; // do not change, part of INotifyPropertyChanged
                const string propertyNameName = "propertyName";

                // event
                writer.WriteEvent(SpecificationDefinition.Public, eventName, typeof(PropertyChangedEventHandler).Name);
                writer.WriteLine();
                // method
                using (writer.WriteMethod(SpecificationDefinition.Protected | SpecificationDefinition.Virtual,
                                          sendPropertyChangedMethod, null, new ParameterDefinition { Name = propertyNameName, Type = typeof(string) }))
                {
                    using (writer.WriteIf(writer.GetDifferentExpression(eventName, writer.GetNullExpression())))
                    {
                        writer.WriteLine(writer.GetStatement(writer.GetMethodCallExpression(eventName,
                                                                                            writer.GetThisExpression(),
                                                                                            writer.GetNewExpression(writer.GetMethodCallExpression(typeof(PropertyChangedEventArgs).Name,
                                                                                                                                                   propertyNameName)))));
                    }
                }
            }
        }

 /// <summary>
 /// Writes class ctor.
 /// EntitySet initializations
 /// </summary>
 /// <param name="writer"></param>
 /// <param name="table"></param>
 /// <param name="schema"></param>
 /// <param name="context"></param>
 protected virtual void WriteClassCtor(CodeWriter writer, Table table, Database schema, GenerationContext context)
 {
     using (writer.WriteRegion("ctor"))
     using (writer.WriteCtor(SpecificationDefinition.Public, table.Type.Name, new ParameterDefinition[0], null))
     {
         // children are EntitySet
         foreach (var child in GetClassChildren(table))
         {
             // if the association has a storage, we use it. Otherwise, we use the property name
             var entitySetMember = child.Storage ?? child.Member;
             writer.WriteLine(writer.GetStatement(
                 writer.GetAssignmentExpression(
                     entitySetMember,
                     writer.GetNewExpression(writer.GetMethodCallExpression(
                         writer.GetGenericName(TypeExtensions.GetShortName(typeof(EntitySet<>)), child.Type),
                         GetChildAttachMethodName(child),
                         GetChildDetachMethodName(child)
                     ))
                 )
                 ));
         }
         // the parents are the entities referenced by a FK. So a "parent" is an EntityRef
         foreach (var parent in GetClassParents(table))
         {
             var entityRefMember = parent.Storage;
             writer.WriteLine(writer.GetStatement(
                 writer.GetAssignmentExpression(
                     entityRefMember,
                     writer.GetNewExpression(writer.GetMethodCallExpression(
                     writer.GetGenericName(TypeExtensions.GetShortName(typeof(EntityRef<>)), parent.Type)
                     ))
                 )
             ));
         }
         writer.WriteLine(writer.GetStatement(writer.GetMethodCallExpression("OnCreated")));
     }
 }

        /// <summary>
        /// Writes property setter, for FK properties
        /// </summary>
        /// <param name="writer"></param>
        /// <param name="property"></param>
        /// <param name="relatedAssociations"></param>
        /// <param name="context"></param>
        private void WriteClassPropertyAccessorSet(CodeWriter writer, Column property, IEnumerable<Association> relatedAssociations, GenerationContext context)
        {
            // if new value if different from old one
            using (writer.WriteIf(writer.GetDifferentExpression(writer.GetPropertySetValueExpression(),
                                                                writer.GetVariableExpression(property.Storage))))
            {
                // if the property is used as a FK, we ensure that it hasn't been already loaded or assigned
                foreach (var relatedAssociation in relatedAssociations)
                {
                    // first thing to check: ensure the association backend isn't already affected.
                    // if it is the case, then the property must not be manually set

                    // R# considers the following as an error, but the csc doesn't
                    //var memberName = ReflectionUtility.GetMemberInfo<DbLinq.Data.Linq.EntityRef<object>>(e => e.HasLoadedOrAssignedValue).Name;
                    var memberName = "HasLoadedOrAssignedValue";
                    using (writer.WriteIf(writer.GetMemberExpression(relatedAssociation.Storage, memberName)))
                    {
                        writer.WriteLine(writer.GetThrowStatement(writer.GetNewExpression(
                                                                      writer.GetMethodCallExpression(
                                                                          writer.GetLiteralFullType(
                                                                              typeof(
                                                                                  System.Data.Linq.
                                                                                  ForeignKeyReferenceAlreadyHasValueException
                                                                                  )))
                                                                      )));
                    }
                }
                // the before and after are used by extensions related to interfaces
                // for example INotifyPropertyChanged
                // here the code before the change
                foreach (IImplementation implementation in context.Implementations())
                    implementation.WritePropertyBeforeSet(writer, property, context);
                // property assignment
                writer.WriteLine(
                    writer.GetStatement(
                        writer.GetAssignmentExpression(writer.GetVariableExpression(property.Storage),
                                                       writer.GetPropertySetValueExpression())));
                // here the code after change
                foreach (IImplementation implementation in context.Implementations())
                    implementation.WritePropertyAfterSet(writer, property, context);
            }
        }