CodeMemberField.InitExpression Propriedade
Definição
Importante
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Obtém ou define a expressão de inicialização para o campo.
public:
property System::CodeDom::CodeExpression ^ InitExpression { System::CodeDom::CodeExpression ^ get(); void set(System::CodeDom::CodeExpression ^ value); };
public System.CodeDom.CodeExpression InitExpression { get; set; }
member this.InitExpression : System.CodeDom.CodeExpression with get, set
Public Property InitExpression As CodeExpression
Valor da propriedade
A expressão de inicialização para o campo.
Exemplos
O exemplo a seguir demonstra o uso da InitExpression propriedade .
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.
/// </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 a field to the class.
/// </summary>
public void AddField()
{
CodeMemberField testField = new CodeMemberField();
testField.Name = "today";
testField.Type = new CodeTypeReference(typeof(System.DateTime));
testField.Attributes = MemberAttributes.Private | MemberAttributes.Static;
testField.InitExpression =
new CodeFieldReferenceExpression(new CodeTypeReferenceExpression("System.DateTime"), "Today");
targetClass.Members.Add(testField);
}
/// <summary>
/// Add a constructor to the class.
/// </summary>
public void AddConstructor()
{
// Declare the constructor
CodeConstructor constructor = new CodeConstructor();
constructor.Attributes =
MemberAttributes.Public | MemberAttributes.Final;
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"));
// Add the statement:
// "CodeDOMCreatedClass testClass =
// new CodeDOMCreatedClass();"
start.Statements.Add(new CodeVariableDeclarationStatement(
new CodeTypeReference("CodeDOMCreatedClass"), "testClass",
objectCreate));
// Creat the expression:
// "testClass.ToString()"
CodeMethodInvokeExpression toStringInvoke =
new CodeMethodInvokeExpression(
new CodeVariableReferenceExpression("today"), "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.AddField();
sample.AddConstructor();
sample.AddEntryPoint();
sample.GenerateCSharpCode(outputFileName);
}
}
}
// A C# code generator produces the following source code for the preceeding example code:
//namespace CodeDOMSample
//{
// using System;
// public sealed class CodeDOMCreatedClass
// {
// private static System.DateTime today = System.DateTime.Today;
// public CodeDOMCreatedClass()
// {
// }
// public static void Main()
// {
// CodeDOMCreatedClass testClass = new CodeDOMCreatedClass();
// System.Console.WriteLine(today.ToString());
// }
// }
//}
Imports System.Reflection
Imports System.IO
Imports System.CodeDom
Imports System.CodeDom.Compiler
Imports Microsoft.CSharp
'/ <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>
Private targetUnit As CodeCompileUnit
'/ <summary>
'/ The only class in the compile unit.
'/ </summary>
Private targetClass As CodeTypeDeclaration
'/ <summary>
'/ The name of the file to contain the source code.
'/ </summary>
Private Const outputFileName As String = "SampleCode.vb"
'/ <summary>
'/ Define the class.
'/ </summary>
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
'/ <summary>
'/ Adds a field to the class.
'/ </summary>
Public Sub AddField()
Dim testField As New CodeMemberField()
testField.Name = "today"
testField.Type = New CodeTypeReference(GetType(System.DateTime))
testField.Attributes = MemberAttributes.Private Or MemberAttributes.Static
testField.InitExpression = New CodeFieldReferenceExpression(New CodeTypeReferenceExpression("System.DateTime"), "Today")
targetClass.Members.Add(testField)
End Sub
'/ <summary>
'/ Add a constructor to the class.
'/ </summary>
Public Sub AddConstructor()
' Declare the constructor
Dim constructor As New CodeConstructor()
constructor.Attributes = MemberAttributes.Public Or MemberAttributes.Final
targetClass.Members.Add(constructor)
End Sub
'/ <summary>
'/ Add an entry point to the class.
'/ </summary>
Public Sub AddEntryPoint()
Dim start As New CodeEntryPointMethod()
Dim objectCreate As New CodeObjectCreateExpression(New CodeTypeReference("CodeDOMCreatedClass"))
' Add the statement:
' "CodeDOMCreatedClass testClass =
' new CodeDOMCreatedClass();"
start.Statements.Add(New CodeVariableDeclarationStatement(New CodeTypeReference("CodeDOMCreatedClass"), "testClass", objectCreate))
' Creat the expression:
' "testClass.ToString()"
Dim toStringInvoke As New CodeMethodInvokeExpression(New CodeVariableReferenceExpression("today"), "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
'/ <summary>
'/ Generate CSharp source code from the compile unit.
'/ </summary>
'/ <param name="filename">Output file name</param>
Public Sub GenerateCSharpCode(ByVal fileName As String)
Dim provider As CodeDomProvider = CodeDomProvider.CreateProvider("VB")
Dim options As New CodeGeneratorOptions()
Dim sourceWriter As New StreamWriter(fileName)
Try
provider.GenerateCodeFromCompileUnit(targetUnit, sourceWriter, options)
Finally
sourceWriter.Dispose()
End Try
End Sub
'/ <summary>
'/ Create the CodeDOM graph and generate the code.
'/ </summary>
Shared Sub Main()
Dim sample As New Sample()
sample.AddField()
sample.AddConstructor()
sample.AddEntryPoint()
sample.GenerateCSharpCode(outputFileName)
End Sub
End Class
' A Visual Basic code generator produces the following source code for the preceeding example code:
'Option Strict Off
'Option Explicit On
''Namespace CodeDOMSample
' Public NotInheritable Class CodeDOMCreatedClass
' Private Shared today As Date = Date.Today
' Public Sub New()
' MyBase.New()
' End Sub
' Public Shared Sub Main()
' Dim testClass As CodeDOMCreatedClass = New CodeDOMCreatedClass
' System.Console.WriteLine(today.ToString)
' End Sub
' End Class
'End Namespace
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