Como: Criar uma classe usando CodeDOM
Os procedimentos a seguir ilustram como criar e compilar um gráfico de CodeDOM gera uma classe contendo dois campos, três propriedades, um método, um construtor e um ponto de entrada.
Crie um aplicativo de console que usará o código de CodeDOM para gerar o código-fonte para uma classe.
Neste exemplo, a classe geradora é nomeada Sample, e o código gerado é uma classe chamada CodeDOMCreatedClass em um arquivo chamado SampleCode.
Na classe geradora, inicializar o gráfico de CodeDOM e use métodos de CodeDOM para definir os membros, construtor e ponto de entrada (Main método) da classe gerada.
Neste exemplo, a classe gerada tem dois campos, três propriedades, um construtor, um método e um Main método.
Na classe geradora, criar um provedor de código de específico a um linguagem e chamar seus GenerateCodeFromCompileUnit método para gerar o código do gráfico.
Compilar e executar o aplicativo para gerar o código.
Neste exemplo, o código gerado é em um arquivo chamado SampleCode.Compilar e executar esse código para ver a saída de exemplo.
Crie uma classe de aplicativo de console para conter o código de CodeDOM.Defina os campos global que devem ser usados na classe para referenciar o assembly (CodeCompileUnit) e de classe ()CodeTypeDeclaration), especifique o nome do arquivo de fonte gerados e declarar o Main método.
Imports System Imports System.Reflection Imports System.IO Imports System.CodeDom Imports System.CodeDom.Compiler Imports Microsoft.CSharp Class Sample Private targetUnit As CodeCompileUnit Private targetClass As CodeTypeDeclaration Private Const outputFileName As String = "SampleCode.cs" Shared Sub Main(ByVal args() As String) End Sub 'Main End Class 'Sample
using System; using System.Reflection; using System.IO; using System.CodeDom; using System.CodeDom.Compiler; using Microsoft.CSharp; namespace SampleCodeDom { class Sample { CodeCompileUnit targetUnit; CodeTypeDeclaration targetClass; private const string outputFileName = "SampleCode.cs"; static void Main(string[] args) { } } }
No construtor da classe de aplicativo de console, inicialize o assembly e a classe e adicionar as declarações apropriadas para o gráfico de CodeDOM.
Public Sub New() targetUnit = New CodeCompileUnit() Dim samples As New CodeNamespace("CodeDOMSample") samples.Imports.Add(New CodeNamespaceImport("System")) targetClass = New CodeTypeDeclaration("CodeDOMCreatedClass") targetClass.IsClass = True targetClass.TypeAttributes = _ TypeAttributes.Public Or TypeAttributes.Sealed samples.Types.Add(targetClass) targetUnit.Namespaces.Add(samples) End Sub 'New
public Sample() { targetUnit = new CodeCompileUnit(); CodeNamespace samples = new CodeNamespace("CodeDOMSample"); samples.Imports.Add(new CodeNamespaceImport("System")); targetClass = new CodeTypeDeclaration("CodeDOMCreatedClass"); targetClass.IsClass = true; targetClass.TypeAttributes = TypeAttributes.Public | TypeAttributes.Sealed; samples.Types.Add(targetClass); targetUnit.Namespaces.Add(samples); }
Adicionar campos ao gráfico CodeDOM adicionando CodeMemberField objetos para o Members propriedade da classe.
Public Sub AddFields() ' Declare the widthValue field. Dim widthValueField As New CodeMemberField() widthValueField.Attributes = MemberAttributes.Private widthValueField.Name = "widthValue" widthValueField.Type = _ New CodeTypeReference(GetType(System.Double)) widthValueField.Comments.Add(New CodeCommentStatement( _ "The width of the object.")) targetClass.Members.Add(widthValueField) ' Declare the heightValue field Dim heightValueField As New CodeMemberField() heightValueField.Attributes = MemberAttributes.Private heightValueField.Name = "heightValue" heightValueField.Type = _ New CodeTypeReference(GetType(System.Double)) heightValueField.Comments.Add(New CodeCommentStatement( _ "The height of the object.")) targetClass.Members.Add(heightValueField) End Sub 'AddFields
public void AddFields() { // Declare the widthValue field. CodeMemberField widthValueField = new CodeMemberField(); widthValueField.Attributes = MemberAttributes.Private; widthValueField.Name = "widthValue"; widthValueField.Type = new CodeTypeReference(typeof(System.Double)); widthValueField.Comments.Add(new CodeCommentStatement( "The width of the object.")); targetClass.Members.Add(widthValueField); // Declare the heightValue field CodeMemberField heightValueField = new CodeMemberField(); heightValueField.Attributes = MemberAttributes.Private; heightValueField.Name = "heightValue"; heightValueField.Type = new CodeTypeReference(typeof(System.Double)); heightValueField.Comments.Add(new CodeCommentStatement( "The height of the object.")); targetClass.Members.Add(heightValueField); }
Adicionar propriedades ao gráfico CodeDOM adicionando CodeMemberProperty objetos para o Members propriedade da classe.
Public Sub AddProperties() ' Declare the read only Width property. Dim widthProperty As New CodeMemberProperty() widthProperty.Attributes = _ MemberAttributes.Public Or MemberAttributes.Final widthProperty.Name = "Width" widthProperty.HasGet = True widthProperty.Type = New CodeTypeReference(GetType(System.Double)) widthProperty.Comments.Add(New CodeCommentStatement( _ "The width property for the object.")) widthProperty.GetStatements.Add(New CodeMethodReturnStatement( _ New CodeFieldReferenceExpression( _ New CodeThisReferenceExpression(), "widthValue"))) targetClass.Members.Add(widthProperty) ' Declare the read-only Height property. Dim heightProperty As New CodeMemberProperty() heightProperty.Attributes = _ MemberAttributes.Public Or MemberAttributes.Final heightProperty.Name = "Height" heightProperty.HasGet = True heightProperty.Type = New CodeTypeReference(GetType(System.Double)) heightProperty.Comments.Add(New CodeCommentStatement( _ "The Height property for the object.")) heightProperty.GetStatements.Add(New CodeMethodReturnStatement( _ New CodeFieldReferenceExpression( _ New CodeThisReferenceExpression(), "heightValue"))) targetClass.Members.Add(heightProperty) ' Declare the read only Area property. Dim areaProperty As New CodeMemberProperty() areaProperty.Attributes = _ MemberAttributes.Public Or MemberAttributes.Final areaProperty.Name = "Area" areaProperty.HasGet = True areaProperty.Type = New CodeTypeReference(GetType(System.Double)) areaProperty.Comments.Add(New CodeCommentStatement( _ "The Area property for the object.")) ' Create an expression to calculate the area for the get accessor ' of the Area property. Dim areaExpression As New CodeBinaryOperatorExpression( _ New CodeFieldReferenceExpression( _ New CodeThisReferenceExpression(), "widthValue"), _ CodeBinaryOperatorType.Multiply, _ New CodeFieldReferenceExpression( _ New CodeThisReferenceExpression(), "heightValue")) areaProperty.GetStatements.Add( _ New CodeMethodReturnStatement(areaExpression)) targetClass.Members.Add(areaProperty) End Sub 'AddProperties
public void AddProperties() { // Declare the read-only Width property. CodeMemberProperty widthProperty = new CodeMemberProperty(); widthProperty.Attributes = MemberAttributes.Public | MemberAttributes.Final; widthProperty.Name = "Width"; widthProperty.HasGet = true; widthProperty.Type = new CodeTypeReference(typeof(System.Double)); widthProperty.Comments.Add(new CodeCommentStatement( "The Width property for the object.")); widthProperty.GetStatements.Add(new CodeMethodReturnStatement( new CodeFieldReferenceExpression( new CodeThisReferenceExpression(), "widthValue"))); targetClass.Members.Add(widthProperty); // Declare the read-only Height property. CodeMemberProperty heightProperty = new CodeMemberProperty(); heightProperty.Attributes = MemberAttributes.Public | MemberAttributes.Final; heightProperty.Name = "Height"; heightProperty.HasGet = true; heightProperty.Type = new CodeTypeReference(typeof(System.Double)); heightProperty.Comments.Add(new CodeCommentStatement( "The Height property for the object.")); heightProperty.GetStatements.Add(new CodeMethodReturnStatement( new CodeFieldReferenceExpression( new CodeThisReferenceExpression(), "heightValue"))); targetClass.Members.Add(heightProperty); // Declare the read only Area property. CodeMemberProperty areaProperty = new CodeMemberProperty(); areaProperty.Attributes = MemberAttributes.Public | MemberAttributes.Final; areaProperty.Name = "Area"; areaProperty.HasGet = true; areaProperty.Type = new CodeTypeReference(typeof(System.Double)); areaProperty.Comments.Add(new CodeCommentStatement( "The Area property for the object.")); // Create an expression to calculate the area for the get accessor // of the Area property. CodeBinaryOperatorExpression areaExpression = new CodeBinaryOperatorExpression( new CodeFieldReferenceExpression( new CodeThisReferenceExpression(), "widthValue"), CodeBinaryOperatorType.Multiply, new CodeFieldReferenceExpression( new CodeThisReferenceExpression(), "heightValue")); areaProperty.GetStatements.Add( new CodeMethodReturnStatement(areaExpression)); targetClass.Members.Add(areaProperty); }
Adicionar um método para o gráfico de CodeDOM adicionando um CodeMemberMethod objeto para o Members propriedade da classe.
Public Sub AddMethod() ' Declaring a ToString method. Dim toStringMethod As New CodeMemberMethod() toStringMethod.Attributes = _ MemberAttributes.Public Or MemberAttributes.Override toStringMethod.Name = "ToString" toStringMethod.ReturnType = _ New CodeTypeReference(GetType(System.String)) Dim widthReference As New CodeFieldReferenceExpression( _ New CodeThisReferenceExpression(), "Width") Dim heightReference As New CodeFieldReferenceExpression( _ New CodeThisReferenceExpression(), "Height") Dim areaReference As New CodeFieldReferenceExpression( _ New CodeThisReferenceExpression(), "Area") ' Declaring a return statement for method ToString. Dim returnStatement As New CodeMethodReturnStatement() ' This statement returns a string representation of the width, ' height, and area. Dim formattedOutput As String = "The object:" & Environment.NewLine _ & " width = {0}," & Environment.NewLine & " height = {1}," _ & Environment.NewLine & " area = {2}" returnStatement.Expression = New CodeMethodInvokeExpression( _ New CodeTypeReferenceExpression("System.String"), "Format", _ New CodePrimitiveExpression(formattedOutput), widthReference, _ heightReference, areaReference) toStringMethod.Statements.Add(returnStatement) targetClass.Members.Add(toStringMethod) End Sub 'AddMethod
public void AddMethod() { // Declaring a ToString method CodeMemberMethod toStringMethod = new CodeMemberMethod(); toStringMethod.Attributes = MemberAttributes.Public | MemberAttributes.Override; toStringMethod.Name = "ToString"; toStringMethod.ReturnType = new CodeTypeReference(typeof(System.String)); CodeFieldReferenceExpression widthReference = new CodeFieldReferenceExpression( new CodeThisReferenceExpression(), "Width"); CodeFieldReferenceExpression heightReference = new CodeFieldReferenceExpression( new CodeThisReferenceExpression(), "Height"); CodeFieldReferenceExpression areaReference = new CodeFieldReferenceExpression( new CodeThisReferenceExpression(), "Area"); // Declaring a return statement for method ToString. CodeMethodReturnStatement returnStatement = new CodeMethodReturnStatement(); // This statement returns a string representation of the width, // height, and area. string formattedOutput = "The object:" + Environment.NewLine + " width = {0}," + Environment.NewLine + " height = {1}," + Environment.NewLine + " area = {2}"; returnStatement.Expression = new CodeMethodInvokeExpression( new CodeTypeReferenceExpression("System.String"), "Format", new CodePrimitiveExpression(formattedOutput), widthReference, heightReference, areaReference); toStringMethod.Statements.Add(returnStatement); targetClass.Members.Add(toStringMethod); }
Adicionar um construtor para o gráfico de CodeDOM adicionando um CodeConstructor objeto para o Members propriedade da classe.
Public Sub AddConstructor() ' Declare the constructor Dim constructor As New CodeConstructor() constructor.Attributes = _ MemberAttributes.Public Or MemberAttributes.Final ' Add parameters. constructor.Parameters.Add( _ New CodeParameterDeclarationExpression( _ GetType(System.Double), "width")) constructor.Parameters.Add( _ New CodeParameterDeclarationExpression( _ GetType(System.Double), "height")) ' Add field initialization logic Dim widthReference As New CodeFieldReferenceExpression( _ New CodeThisReferenceExpression(), "widthValue") constructor.Statements.Add(New CodeAssignStatement( _ widthReference, New CodeArgumentReferenceExpression("width"))) Dim heightReference As New CodeFieldReferenceExpression( _ New CodeThisReferenceExpression(), "heightValue") constructor.Statements.Add( _ New CodeAssignStatement(heightReference, _ New CodeArgumentReferenceExpression("height"))) targetClass.Members.Add(constructor) End Sub 'AddConstructor
public void AddConstructor() { // Declare the constructor CodeConstructor constructor = new CodeConstructor(); constructor.Attributes = MemberAttributes.Public | MemberAttributes.Final; // Add parameters. constructor.Parameters.Add(new CodeParameterDeclarationExpression( typeof(System.Double), "width")); constructor.Parameters.Add(new CodeParameterDeclarationExpression( typeof(System.Double), "height")); // Add field initialization logic CodeFieldReferenceExpression widthReference = new CodeFieldReferenceExpression( new CodeThisReferenceExpression(), "widthValue"); constructor.Statements.Add(new CodeAssignStatement(widthReference, new CodeArgumentReferenceExpression("width"))); CodeFieldReferenceExpression heightReference = new CodeFieldReferenceExpression( new CodeThisReferenceExpression(), "heightValue"); constructor.Statements.Add(new CodeAssignStatement(heightReference, new CodeArgumentReferenceExpression("height"))); targetClass.Members.Add(constructor); }
Adicionar um ponto de entrada para o gráfico de CodeDOM adicionando um CodeEntryPointMethod objeto para o Members propriedade da classe.
Public Sub AddEntryPoint() Dim start As New CodeEntryPointMethod() Dim objectCreate As New CodeObjectCreateExpression( _ New CodeTypeReference("CodeDOMCreatedClass"), _ New CodePrimitiveExpression(5.3), _ New CodePrimitiveExpression(6.9)) ' Add the statement: ' "CodeDOMCreatedClass testClass = _ ' new CodeDOMCreatedClass(5.3, 6.9);" start.Statements.Add(New CodeVariableDeclarationStatement( _ New CodeTypeReference("CodeDOMCreatedClass"), _ "testClass", objectCreate)) ' Creat the expression: ' "testClass.ToString()" Dim toStringInvoke As New CodeMethodInvokeExpression( _ New CodeVariableReferenceExpression("testClass"), "ToString") ' Add a System.Console.WriteLine statement with the previous ' expression as a parameter. start.Statements.Add(New CodeMethodInvokeExpression( _ New CodeTypeReferenceExpression("System.Console"), _ "WriteLine", toStringInvoke)) targetClass.Members.Add(start) End Sub 'AddEntryPoint
public void AddEntryPoint() { CodeEntryPointMethod start = new CodeEntryPointMethod(); CodeObjectCreateExpression objectCreate = new CodeObjectCreateExpression( new CodeTypeReference("CodeDOMCreatedClass"), new CodePrimitiveExpression(5.3), new CodePrimitiveExpression(6.9)); // Add the statement: // "CodeDOMCreatedClass testClass = // new CodeDOMCreatedClass(5.3, 6.9);" start.Statements.Add(new CodeVariableDeclarationStatement( new CodeTypeReference("CodeDOMCreatedClass"), "testClass", objectCreate)); // Creat the expression: // "testClass.ToString()" CodeMethodInvokeExpression toStringInvoke = new CodeMethodInvokeExpression( new CodeVariableReferenceExpression("testClass"), "ToString"); // Add a System.Console.WriteLine statement with the previous // expression as a parameter. start.Statements.Add(new CodeMethodInvokeExpression( new CodeTypeReferenceExpression("System.Console"), "WriteLine", toStringInvoke)); targetClass.Members.Add(start); }
Gerar código-fonte do gráfico CodeDOM chamando o GenerateCodeFromCompileUnit método.
Public Sub GenerateVBCode(ByVal fileName As String) Dim provider As CodeDomProvider provider = CodeDomProvider.CreateProvider("VisualBasic") Dim options As New CodeGeneratorOptions() Dim sourceWriter As New StreamWriter(fileName) Try provider.GenerateCodeFromCompileUnit( _ targetUnit, sourceWriter, options) Finally sourceWriter.Dispose() End Try End Sub 'GenerateVBCode
public void GenerateCSharpCode(string fileName) { CodeDomProvider provider = CodeDomProvider.CreateProvider("CSharp"); CodeGeneratorOptions options = new CodeGeneratorOptions(); options.BracingStyle = "C"; using (StreamWriter sourceWriter = new StreamWriter(fileName)) { provider.GenerateCodeFromCompileUnit( targetUnit, sourceWriter, options); } }
Adicione métodos criados nas etapas anteriores para o Main método definido na primeira etapa.
Shared Sub Main() Dim sample As New Sample() sample.AddFields() sample.AddProperties() sample.AddMethod() sample.AddConstructor() sample.AddEntryPoint() sample.GenerateVBCode(outputFileName) End Sub 'Main End Class 'Sample
static void Main() { Sample sample = new Sample(); sample.AddFields(); sample.AddProperties(); sample.AddMethod(); sample.AddConstructor(); sample.AddEntryPoint(); sample.GenerateCSharpCode(outputFileName); }
Compilar e executar a classe geradora.
O exemplo de código a seguir mostra o código das etapas anteriores.
Imports System
Imports System.Reflection
Imports System.IO
Imports System.CodeDom
Imports System.CodeDom.Compiler
Imports Microsoft.VisualBasic
' This code example creates a graph using a CodeCompileUnit and
' generates source code for the graph using the VBCodeProvider.
Class Sample
' Define the compile unit to use for code generation.
Private targetUnit As CodeCompileUnit
' The only class in the compile unit. This class contains 2 fields,
' 3 properties, a constructor, an entry point, and 1 simple method.
Private targetClass As CodeTypeDeclaration
' The name of the file to contain the source code.
Private Const outputFileName As String = "SampleCode.vb"
' Define the class.
Public Sub New()
targetUnit = New CodeCompileUnit()
Dim samples As New CodeNamespace("CodeDOMSample")
samples.Imports.Add(New CodeNamespaceImport("System"))
targetClass = New CodeTypeDeclaration("CodeDOMCreatedClass")
targetClass.IsClass = True
targetClass.TypeAttributes = _
TypeAttributes.Public Or TypeAttributes.Sealed
samples.Types.Add(targetClass)
targetUnit.Namespaces.Add(samples)
End Sub 'New
' Adds two fields to the class.
Public Sub AddFields()
' Declare the widthValue field.
Dim widthValueField As New CodeMemberField()
widthValueField.Attributes = MemberAttributes.Private
widthValueField.Name = "widthValue"
widthValueField.Type = _
New CodeTypeReference(GetType(System.Double))
widthValueField.Comments.Add(New CodeCommentStatement( _
"The width of the object."))
targetClass.Members.Add(widthValueField)
' Declare the heightValue field
Dim heightValueField As New CodeMemberField()
heightValueField.Attributes = MemberAttributes.Private
heightValueField.Name = "heightValue"
heightValueField.Type = _
New CodeTypeReference(GetType(System.Double))
heightValueField.Comments.Add(New CodeCommentStatement( _
"The height of the object."))
targetClass.Members.Add(heightValueField)
End Sub 'AddFields
' Add three properties to the class.
Public Sub AddProperties()
' Declare the read only Width property.
Dim widthProperty As New CodeMemberProperty()
widthProperty.Attributes = _
MemberAttributes.Public Or MemberAttributes.Final
widthProperty.Name = "Width"
widthProperty.HasGet = True
widthProperty.Type = New CodeTypeReference(GetType(System.Double))
widthProperty.Comments.Add(New CodeCommentStatement( _
"The width property for the object."))
widthProperty.GetStatements.Add(New CodeMethodReturnStatement( _
New CodeFieldReferenceExpression( _
New CodeThisReferenceExpression(), "widthValue")))
targetClass.Members.Add(widthProperty)
' Declare the read-only Height property.
Dim heightProperty As New CodeMemberProperty()
heightProperty.Attributes = _
MemberAttributes.Public Or MemberAttributes.Final
heightProperty.Name = "Height"
heightProperty.HasGet = True
heightProperty.Type = New CodeTypeReference(GetType(System.Double))
heightProperty.Comments.Add(New CodeCommentStatement( _
"The Height property for the object."))
heightProperty.GetStatements.Add(New CodeMethodReturnStatement( _
New CodeFieldReferenceExpression( _
New CodeThisReferenceExpression(), "heightValue")))
targetClass.Members.Add(heightProperty)
' Declare the read only Area property.
Dim areaProperty As New CodeMemberProperty()
areaProperty.Attributes = _
MemberAttributes.Public Or MemberAttributes.Final
areaProperty.Name = "Area"
areaProperty.HasGet = True
areaProperty.Type = New CodeTypeReference(GetType(System.Double))
areaProperty.Comments.Add(New CodeCommentStatement( _
"The Area property for the object."))
' Create an expression to calculate the area for the get accessor
' of the Area property.
Dim areaExpression As New CodeBinaryOperatorExpression( _
New CodeFieldReferenceExpression( _
New CodeThisReferenceExpression(), "widthValue"), _
CodeBinaryOperatorType.Multiply, _
New CodeFieldReferenceExpression( _
New CodeThisReferenceExpression(), "heightValue"))
areaProperty.GetStatements.Add( _
New CodeMethodReturnStatement(areaExpression))
targetClass.Members.Add(areaProperty)
End Sub 'AddProperties
' Adds a method to the class. This method multiplies values stored
' in both fields.
Public Sub AddMethod()
' Declaring a ToString method.
Dim toStringMethod As New CodeMemberMethod()
toStringMethod.Attributes = _
MemberAttributes.Public Or MemberAttributes.Override
toStringMethod.Name = "ToString"
toStringMethod.ReturnType = _
New CodeTypeReference(GetType(System.String))
Dim widthReference As New CodeFieldReferenceExpression( _
New CodeThisReferenceExpression(), "Width")
Dim heightReference As New CodeFieldReferenceExpression( _
New CodeThisReferenceExpression(), "Height")
Dim areaReference As New CodeFieldReferenceExpression( _
New CodeThisReferenceExpression(), "Area")
' Declaring a return statement for method ToString.
Dim returnStatement As New CodeMethodReturnStatement()
' This statement returns a string representation of the width,
' height, and area.
Dim formattedOutput As String = "The object:" & Environment.NewLine _
& " width = {0}," & Environment.NewLine & " height = {1}," _
& Environment.NewLine & " area = {2}"
returnStatement.Expression = New CodeMethodInvokeExpression( _
New CodeTypeReferenceExpression("System.String"), "Format", _
New CodePrimitiveExpression(formattedOutput), widthReference, _
heightReference, areaReference)
toStringMethod.Statements.Add(returnStatement)
targetClass.Members.Add(toStringMethod)
End Sub 'AddMethod
' Add a constructor to the class.
Public Sub AddConstructor()
' Declare the constructor
Dim constructor As New CodeConstructor()
constructor.Attributes = _
MemberAttributes.Public Or MemberAttributes.Final
' Add parameters.
constructor.Parameters.Add( _
New CodeParameterDeclarationExpression( _
GetType(System.Double), "width"))
constructor.Parameters.Add( _
New CodeParameterDeclarationExpression( _
GetType(System.Double), "height"))
' Add field initialization logic
Dim widthReference As New CodeFieldReferenceExpression( _
New CodeThisReferenceExpression(), "widthValue")
constructor.Statements.Add(New CodeAssignStatement( _
widthReference, New CodeArgumentReferenceExpression("width")))
Dim heightReference As New CodeFieldReferenceExpression( _
New CodeThisReferenceExpression(), "heightValue")
constructor.Statements.Add( _
New CodeAssignStatement(heightReference, _
New CodeArgumentReferenceExpression("height")))
targetClass.Members.Add(constructor)
End Sub 'AddConstructor
' Add an entry point to the class.
Public Sub AddEntryPoint()
Dim start As New CodeEntryPointMethod()
Dim objectCreate As New CodeObjectCreateExpression( _
New CodeTypeReference("CodeDOMCreatedClass"), _
New CodePrimitiveExpression(5.3), _
New CodePrimitiveExpression(6.9))
' Add the statement:
' "CodeDOMCreatedClass testClass = _
' new CodeDOMCreatedClass(5.3, 6.9);"
start.Statements.Add(New CodeVariableDeclarationStatement( _
New CodeTypeReference("CodeDOMCreatedClass"), _
"testClass", objectCreate))
' Creat the expression:
' "testClass.ToString()"
Dim toStringInvoke As New CodeMethodInvokeExpression( _
New CodeVariableReferenceExpression("testClass"), "ToString")
' Add a System.Console.WriteLine statement with the previous
' expression as a parameter.
start.Statements.Add(New CodeMethodInvokeExpression( _
New CodeTypeReferenceExpression("System.Console"), _
"WriteLine", toStringInvoke))
targetClass.Members.Add(start)
End Sub 'AddEntryPoint
' Generate Visual Basic source code from the compile unit.
Public Sub GenerateVBCode(ByVal fileName As String)
Dim provider As CodeDomProvider
provider = CodeDomProvider.CreateProvider("VisualBasic")
Dim options As New CodeGeneratorOptions()
Dim sourceWriter As New StreamWriter(fileName)
Try
provider.GenerateCodeFromCompileUnit( _
targetUnit, sourceWriter, options)
Finally
sourceWriter.Dispose()
End Try
End Sub 'GenerateVBCode
' Create the CodeDOM graph and generate the code.
Shared Sub Main()
Dim sample As New Sample()
sample.AddFields()
sample.AddProperties()
sample.AddMethod()
sample.AddConstructor()
sample.AddEntryPoint()
sample.GenerateVBCode(outputFileName)
End Sub 'Main
End Class 'Sample
using System;
using System.Reflection;
using System.IO;
using System.CodeDom;
using System.CodeDom.Compiler;
using Microsoft.CSharp;
namespace SampleCodeDom
{
/// <summary>
/// This code example creates a graph using a CodeCompileUnit and
/// generates source code for the graph using the CSharpCodeProvider.
/// </summary>
class Sample
{
/// <summary>
/// Define the compile unit to use for code generation.
/// </summary>
CodeCompileUnit targetUnit;
/// <summary>
/// The only class in the compile unit. This class contains 2 fields,
/// 3 properties, a constructor, an entry point, and 1 simple method.
/// </summary>
CodeTypeDeclaration targetClass;
/// <summary>
/// The name of the file to contain the source code.
/// </summary>
private const string outputFileName = "SampleCode.cs";
/// <summary>
/// Define the class.
/// </summary>
public Sample()
{
targetUnit = new CodeCompileUnit();
CodeNamespace samples = new CodeNamespace("CodeDOMSample");
samples.Imports.Add(new CodeNamespaceImport("System"));
targetClass = new CodeTypeDeclaration("CodeDOMCreatedClass");
targetClass.IsClass = true;
targetClass.TypeAttributes =
TypeAttributes.Public | TypeAttributes.Sealed;
samples.Types.Add(targetClass);
targetUnit.Namespaces.Add(samples);
}
/// <summary>
/// Adds two fields to the class.
/// </summary>
public void AddFields()
{
// Declare the widthValue field.
CodeMemberField widthValueField = new CodeMemberField();
widthValueField.Attributes = MemberAttributes.Private;
widthValueField.Name = "widthValue";
widthValueField.Type = new CodeTypeReference(typeof(System.Double));
widthValueField.Comments.Add(new CodeCommentStatement(
"The width of the object."));
targetClass.Members.Add(widthValueField);
// Declare the heightValue field
CodeMemberField heightValueField = new CodeMemberField();
heightValueField.Attributes = MemberAttributes.Private;
heightValueField.Name = "heightValue";
heightValueField.Type =
new CodeTypeReference(typeof(System.Double));
heightValueField.Comments.Add(new CodeCommentStatement(
"The height of the object."));
targetClass.Members.Add(heightValueField);
}
/// <summary>
/// Add three properties to the class.
/// </summary>
public void AddProperties()
{
// Declare the read-only Width property.
CodeMemberProperty widthProperty = new CodeMemberProperty();
widthProperty.Attributes =
MemberAttributes.Public | MemberAttributes.Final;
widthProperty.Name = "Width";
widthProperty.HasGet = true;
widthProperty.Type = new CodeTypeReference(typeof(System.Double));
widthProperty.Comments.Add(new CodeCommentStatement(
"The Width property for the object."));
widthProperty.GetStatements.Add(new CodeMethodReturnStatement(
new CodeFieldReferenceExpression(
new CodeThisReferenceExpression(), "widthValue")));
targetClass.Members.Add(widthProperty);
// Declare the read-only Height property.
CodeMemberProperty heightProperty = new CodeMemberProperty();
heightProperty.Attributes =
MemberAttributes.Public | MemberAttributes.Final;
heightProperty.Name = "Height";
heightProperty.HasGet = true;
heightProperty.Type = new CodeTypeReference(typeof(System.Double));
heightProperty.Comments.Add(new CodeCommentStatement(
"The Height property for the object."));
heightProperty.GetStatements.Add(new CodeMethodReturnStatement(
new CodeFieldReferenceExpression(
new CodeThisReferenceExpression(), "heightValue")));
targetClass.Members.Add(heightProperty);
// Declare the read only Area property.
CodeMemberProperty areaProperty = new CodeMemberProperty();
areaProperty.Attributes =
MemberAttributes.Public | MemberAttributes.Final;
areaProperty.Name = "Area";
areaProperty.HasGet = true;
areaProperty.Type = new CodeTypeReference(typeof(System.Double));
areaProperty.Comments.Add(new CodeCommentStatement(
"The Area property for the object."));
// Create an expression to calculate the area for the get accessor
// of the Area property.
CodeBinaryOperatorExpression areaExpression =
new CodeBinaryOperatorExpression(
new CodeFieldReferenceExpression(
new CodeThisReferenceExpression(), "widthValue"),
CodeBinaryOperatorType.Multiply,
new CodeFieldReferenceExpression(
new CodeThisReferenceExpression(), "heightValue"));
areaProperty.GetStatements.Add(
new CodeMethodReturnStatement(areaExpression));
targetClass.Members.Add(areaProperty);
}
/// <summary>
/// Adds a method to the class. This method multiplies values stored
/// in both fields.
/// </summary>
public void AddMethod()
{
// Declaring a ToString method
CodeMemberMethod toStringMethod = new CodeMemberMethod();
toStringMethod.Attributes =
MemberAttributes.Public | MemberAttributes.Override;
toStringMethod.Name = "ToString";
toStringMethod.ReturnType =
new CodeTypeReference(typeof(System.String));
CodeFieldReferenceExpression widthReference =
new CodeFieldReferenceExpression(
new CodeThisReferenceExpression(), "Width");
CodeFieldReferenceExpression heightReference =
new CodeFieldReferenceExpression(
new CodeThisReferenceExpression(), "Height");
CodeFieldReferenceExpression areaReference =
new CodeFieldReferenceExpression(
new CodeThisReferenceExpression(), "Area");
// Declaring a return statement for method ToString.
CodeMethodReturnStatement returnStatement =
new CodeMethodReturnStatement();
// This statement returns a string representation of the width,
// height, and area.
string formattedOutput = "The object:" + Environment.NewLine +
" width = {0}," + Environment.NewLine +
" height = {1}," + Environment.NewLine +
" area = {2}";
returnStatement.Expression =
new CodeMethodInvokeExpression(
new CodeTypeReferenceExpression("System.String"), "Format",
new CodePrimitiveExpression(formattedOutput),
widthReference, heightReference, areaReference);
toStringMethod.Statements.Add(returnStatement);
targetClass.Members.Add(toStringMethod);
}
/// <summary>
/// Add a constructor to the class.
/// </summary>
public void AddConstructor()
{
// Declare the constructor
CodeConstructor constructor = new CodeConstructor();
constructor.Attributes =
MemberAttributes.Public | MemberAttributes.Final;
// Add parameters.
constructor.Parameters.Add(new CodeParameterDeclarationExpression(
typeof(System.Double), "width"));
constructor.Parameters.Add(new CodeParameterDeclarationExpression(
typeof(System.Double), "height"));
// Add field initialization logic
CodeFieldReferenceExpression widthReference =
new CodeFieldReferenceExpression(
new CodeThisReferenceExpression(), "widthValue");
constructor.Statements.Add(new CodeAssignStatement(widthReference,
new CodeArgumentReferenceExpression("width")));
CodeFieldReferenceExpression heightReference =
new CodeFieldReferenceExpression(
new CodeThisReferenceExpression(), "heightValue");
constructor.Statements.Add(new CodeAssignStatement(heightReference,
new CodeArgumentReferenceExpression("height")));
targetClass.Members.Add(constructor);
}
/// <summary>
/// Add an entry point to the class.
/// </summary>
public void AddEntryPoint()
{
CodeEntryPointMethod start = new CodeEntryPointMethod();
CodeObjectCreateExpression objectCreate =
new CodeObjectCreateExpression(
new CodeTypeReference("CodeDOMCreatedClass"),
new CodePrimitiveExpression(5.3),
new CodePrimitiveExpression(6.9));
// Add the statement:
// "CodeDOMCreatedClass testClass =
// new CodeDOMCreatedClass(5.3, 6.9);"
start.Statements.Add(new CodeVariableDeclarationStatement(
new CodeTypeReference("CodeDOMCreatedClass"), "testClass",
objectCreate));
// Creat the expression:
// "testClass.ToString()"
CodeMethodInvokeExpression toStringInvoke =
new CodeMethodInvokeExpression(
new CodeVariableReferenceExpression("testClass"), "ToString");
// Add a System.Console.WriteLine statement with the previous
// expression as a parameter.
start.Statements.Add(new CodeMethodInvokeExpression(
new CodeTypeReferenceExpression("System.Console"),
"WriteLine", toStringInvoke));
targetClass.Members.Add(start);
}
/// <summary>
/// Generate CSharp source code from the compile unit.
/// </summary>
/// <param name="filename">Output file name</param>
public void GenerateCSharpCode(string fileName)
{
CodeDomProvider provider = CodeDomProvider.CreateProvider("CSharp");
CodeGeneratorOptions options = new CodeGeneratorOptions();
options.BracingStyle = "C";
using (StreamWriter sourceWriter = new StreamWriter(fileName))
{
provider.GenerateCodeFromCompileUnit(
targetUnit, sourceWriter, options);
}
}
/// <summary>
/// Create the CodeDOM graph and generate the code.
/// </summary>
static void Main()
{
Sample sample = new Sample();
sample.AddFields();
sample.AddProperties();
sample.AddMethod();
sample.AddConstructor();
sample.AddEntryPoint();
sample.GenerateCSharpCode(outputFileName);
}
}
}
Quando o exemplo anterior é compilado e executado, ele produz o seguinte código-fonte.
'--------------------------------------------------------------------------
' <auto-generated>
' This code was generated by a tool.
' Runtime Version:2.0.50727.42
'
' Changes to this file may cause incorrect behavior and will be lost if
' the code is regenerated.
' </auto-generated>
'--------------------------------------------------------------------------
Option Strict Off
Option Explicit On
Imports System
Namespace CodeDOMSample
Public NotInheritable Class CodeDOMCreatedClass
'The width of the object.
Private widthValue As Double
'The height of the object.
Private heightValue As Double
Public Sub New(ByVal width As Double, ByVal height As Double)
MyBase.New
Me.widthValue = width
Me.heightValue = height
End Sub
'The width property for the object.
Public ReadOnly Property Width() As Double
Get
Return Me.widthValue
End Get
End Property
'The Height property for the object.
Public ReadOnly Property Height() As Double
Get
Return Me.heightValue
End Get
End Property
'The Area property for the object.
Public ReadOnly Property Area() As Double
Get
Return (Me.widthValue * Me.heightValue)
End Get
End Property
Public Overrides Function ToString() As String
Return String.Format("The object:"& _
Global.Microsoft.VisualBasic.ChrW(13)& _
Global.Microsoft.VisualBasic.ChrW(10)& _
" width = {0},"&Global.Microsoft.VisualBasic.ChrW(13)& _
Global.Microsoft.VisualBasic.ChrW(10)& _
" height = {1},"&Global.Microsoft.VisualBasic.ChrW(13)& _
Global.Microsoft.VisualBasic.ChrW(10)&" area = {2}", _
Me.Width, Me.Height, Me.Area)
End Function
Public Shared Sub Main()
Dim testClass As CodeDOMCreatedClass = _
New CodeDOMCreatedClass(5.3, 6.9)
System.Console.WriteLine(testClass.ToString)
End Sub
End Class
End Namespace
//--------------------------------------------------------------------------
// <auto-generated>
// This code was generated by a tool.
// Runtime Version:2.0.50727.42
//
// Changes to this file may cause incorrect behavior and will be lost if
// the code is regenerated.
// </auto-generated>
//--------------------------------------------------------------------------
namespace CodeDOMSample
{
using System;
public sealed class CodeDOMCreatedClass
{
// The width of the object.
private double widthValue;
// The height of the object.
private double heightValue;
public CodeDOMCreatedClass(double width, double height)
{
this.widthValue = width;
this.heightValue = height;
}
// The Width property for the object.
public double Width
{
get
{
return this.widthValue;
}
}
// The Height property for the object.
public double Height
{
get
{
return this.heightValue;
}
}
// The Area property for the object.
public double Area
{
get
{
return (this.widthValue * this.heightValue);
}
}
public override string ToString()
{
return string.Format(
"The object:\r\n width = {0},\r\n height = {1},\r\n area = {2}",
this.Width, this.Height, this.Area);
}
public static void Main()
{
CodeDOMCreatedClass testClass = new CodeDOMCreatedClass(5.3, 6.9);
System.Console.WriteLine(testClass.ToString());
}
}
}
O código-fonte gerado produz a seguinte saída quando compilado e executado.
The object:
width = 5.3,
height = 6.9,
area = 36.57
- Este exemplo de código requer a FullTrust conjunto permissão para executar com êxito.
Gerando código-fonte e compilando um programa de um gráfico de CodeDOM