PropertyBuilder-Klasse
Definiert die Eigenschaften für einen Typ.
Namespace: System.Reflection.Emit
Assembly: mscorlib (in mscorlib.dll)
Syntax
'Declaration
<ClassInterfaceAttribute(ClassInterfaceType.None)> _
<ComVisibleAttribute(True)> _
Public NotInheritable Class PropertyBuilder
Inherits PropertyInfo
Implements _PropertyBuilder
'Usage
Dim instance As PropertyBuilder
[ClassInterfaceAttribute(ClassInterfaceType.None)]
[ComVisibleAttribute(true)]
public sealed class PropertyBuilder : PropertyInfo, _PropertyBuilder
[ClassInterfaceAttribute(ClassInterfaceType::None)]
[ComVisibleAttribute(true)]
public ref class PropertyBuilder sealed : public PropertyInfo, _PropertyBuilder
/** @attribute ClassInterfaceAttribute(ClassInterfaceType.None) */
/** @attribute ComVisibleAttribute(true) */
public final class PropertyBuilder extends PropertyInfo implements _PropertyBuilder
ClassInterfaceAttribute(ClassInterfaceType.None)
ComVisibleAttribute(true)
public final class PropertyBuilder extends PropertyInfo implements _PropertyBuilder
Hinweise
Hinweis
Das auf diese Klasse angewendete HostProtectionAttribute-Attribut besitzt den Resources-Eigenschaftenwert MayLeakOnAbort. Das HostProtectionAttribute hat keine Auswirkungen auf Desktopanwendungen (die normalerweise durch Doppelklicken auf ein Symbol, Eingeben eines Befehls oder eines URL in einem Browser gestartet werden). Weitere Informationen finden Sie unter der HostProtectionAttribute-Klasse oder unter SQL Server-Programmierung und Hostschutzattribute.
Ein PropertyBuilder ist immer einem TypeBuilder zugeordnet. Der TypeBuilder. DieDefineProperty-Methode gibt einen neuen PropertyBuilder an einen Client zurück.
Beispiel
Das folgende Codebeispiel veranschaulicht die Implementierung von Eigenschaften in einem dynamischen Typ mit einem über TypeBuilder.DefineProperty abgerufenen PropertyBuilder zum Erstellen des Eigenschaftenframeworks und einem zugeordneten MethodBuilder zum Implementieren der IL-Logik innerhalb der Eigenschaft.
Imports System
Imports System.Threading
Imports System.Reflection
Imports System.Reflection.Emit
Class PropertyBuilderDemo
Public Shared Function BuildDynamicTypeWithProperties() As Type
Dim myDomain As AppDomain = Thread.GetDomain()
Dim myAsmName As New AssemblyName()
myAsmName.Name = "MyDynamicAssembly"
' To generate a persistable assembly, specify AssemblyBuilderAccess.RunAndSave.
Dim myAsmBuilder As AssemblyBuilder = myDomain.DefineDynamicAssembly(myAsmName, _
AssemblyBuilderAccess.RunAndSave)
' Generate a persistable, single-module assembly.
Dim myModBuilder As ModuleBuilder = _
myAsmBuilder.DefineDynamicModule(myAsmName.Name, myAsmName.Name & ".dll")
Dim myTypeBuilder As TypeBuilder = myModBuilder.DefineType("CustomerData", TypeAttributes.Public)
' Define a private field to hold the property value.
Dim customerNameBldr As FieldBuilder = myTypeBuilder.DefineField("customerName", _
GetType(String), FieldAttributes.Private)
' The last argument of DefineProperty is Nothing, because the
' property has no parameters. (If you don't specify Nothing, you must
' specify an array of Type objects. For a parameterless property,
' use an array with no elements: New Type() {})
Dim custNamePropBldr As PropertyBuilder = _
myTypeBuilder.DefineProperty("CustomerName", _
PropertyAttributes.HasDefault, _
GetType(String), _
Nothing)
' The property set and property get methods require a special
' set of attributes.
Dim getSetAttr As MethodAttributes = _
MethodAttributes.Public Or MethodAttributes.SpecialName _
Or MethodAttributes.HideBySig
' Define the "get" accessor method for CustomerName.
Dim custNameGetPropMthdBldr As MethodBuilder = _
myTypeBuilder.DefineMethod("GetCustomerName", _
getSetAttr, _
GetType(String), _
Type.EmptyTypes)
Dim custNameGetIL As ILGenerator = custNameGetPropMthdBldr.GetILGenerator()
custNameGetIL.Emit(OpCodes.Ldarg_0)
custNameGetIL.Emit(OpCodes.Ldfld, customerNameBldr)
custNameGetIL.Emit(OpCodes.Ret)
' Define the "set" accessor method for CustomerName.
Dim custNameSetPropMthdBldr As MethodBuilder = _
myTypeBuilder.DefineMethod("get_CustomerName", _
getSetAttr, _
Nothing, _
New Type() {GetType(String)})
Dim custNameSetIL As ILGenerator = custNameSetPropMthdBldr.GetILGenerator()
custNameSetIL.Emit(OpCodes.Ldarg_0)
custNameSetIL.Emit(OpCodes.Ldarg_1)
custNameSetIL.Emit(OpCodes.Stfld, customerNameBldr)
custNameSetIL.Emit(OpCodes.Ret)
' Last, we must map the two methods created above to our PropertyBuilder to
' their corresponding behaviors, "get" and "set" respectively.
custNamePropBldr.SetGetMethod(custNameGetPropMthdBldr)
custNamePropBldr.SetSetMethod(custNameSetPropMthdBldr)
Dim retval As Type = myTypeBuilder.CreateType()
' Save the assembly so it can be examined with Ildasm.exe,
' or referenced by a test program.
myAsmBuilder.Save(myAsmName.Name & ".dll")
return retval
End Function 'BuildDynamicTypeWithProperties
Public Shared Sub Main()
Dim custDataType As Type = BuildDynamicTypeWithProperties()
Dim custDataPropInfo As PropertyInfo() = custDataType.GetProperties()
Dim pInfo As PropertyInfo
For Each pInfo In custDataPropInfo
Console.WriteLine("Property '{0}' created!", pInfo.ToString())
Next pInfo
Console.WriteLine("---")
' Note that when invoking a property, you need to use the proper BindingFlags -
' BindingFlags.SetProperty when you invoke the "set" behavior, and
' BindingFlags.GetProperty when you invoke the "get" behavior. Also note that
' we invoke them based on the name we gave the property, as expected, and not
' the name of the methods we bound to the specific property behaviors.
Dim custData As Object = Activator.CreateInstance(custDataType)
custDataType.InvokeMember("CustomerName", BindingFlags.SetProperty, Nothing, _
custData, New Object() {"Joe User"})
Console.WriteLine("The customerName field of instance custData has been set to '{0}'.", _
custDataType.InvokeMember("CustomerName", BindingFlags.GetProperty, _
Nothing, custData, New Object() {}))
End Sub 'Main
End Class 'PropertyBuilderDemo
' --- O U T P U T ---
' The output should be as follows:
' -------------------
' Property 'System.String CustomerName [System.String]' created!
' ---
' The customerName field of instance custData has been set to 'Joe User'.
' -------------------
using System;
using System.Threading;
using System.Reflection;
using System.Reflection.Emit;
class PropertyBuilderDemo
{
public static Type BuildDynamicTypeWithProperties()
{
AppDomain myDomain = Thread.GetDomain();
AssemblyName myAsmName = new AssemblyName();
myAsmName.Name = "MyDynamicAssembly";
// To generate a persistable assembly, specify AssemblyBuilderAccess.RunAndSave.
AssemblyBuilder myAsmBuilder = myDomain.DefineDynamicAssembly(myAsmName,
AssemblyBuilderAccess.RunAndSave);
// Generate a persistable single-module assembly.
ModuleBuilder myModBuilder =
myAsmBuilder.DefineDynamicModule(myAsmName.Name, myAsmName.Name + ".dll");
TypeBuilder myTypeBuilder = myModBuilder.DefineType("CustomerData",
TypeAttributes.Public);
FieldBuilder customerNameBldr = myTypeBuilder.DefineField("customerName",
typeof(string),
FieldAttributes.Private);
// The last argument of DefineProperty is null, because the
// property has no parameters. (If you don't specify null, you must
// specify an array of Type objects. For a parameterless property,
// use an array with no elements: new Type[] {})
PropertyBuilder custNamePropBldr = myTypeBuilder.DefineProperty("CustomerName",
PropertyAttributes.HasDefault,
typeof(string),
null);
// The property set and property get methods require a special
// set of attributes.
MethodAttributes getSetAttr =
MethodAttributes.Public | MethodAttributes.SpecialName |
MethodAttributes.HideBySig;
// Define the "get" accessor method for CustomerName.
MethodBuilder custNameGetPropMthdBldr =
myTypeBuilder.DefineMethod("get_CustomerName",
getSetAttr,
typeof(string),
Type.EmptyTypes);
ILGenerator custNameGetIL = custNameGetPropMthdBldr.GetILGenerator();
custNameGetIL.Emit(OpCodes.Ldarg_0);
custNameGetIL.Emit(OpCodes.Ldfld, customerNameBldr);
custNameGetIL.Emit(OpCodes.Ret);
// Define the "set" accessor method for CustomerName.
MethodBuilder custNameSetPropMthdBldr =
myTypeBuilder.DefineMethod("set_CustomerName",
getSetAttr,
null,
new Type[] { typeof(string) });
ILGenerator custNameSetIL = custNameSetPropMthdBldr.GetILGenerator();
custNameSetIL.Emit(OpCodes.Ldarg_0);
custNameSetIL.Emit(OpCodes.Ldarg_1);
custNameSetIL.Emit(OpCodes.Stfld, customerNameBldr);
custNameSetIL.Emit(OpCodes.Ret);
// Last, we must map the two methods created above to our PropertyBuilder to
// their corresponding behaviors, "get" and "set" respectively.
custNamePropBldr.SetGetMethod(custNameGetPropMthdBldr);
custNamePropBldr.SetSetMethod(custNameSetPropMthdBldr);
Type retval = myTypeBuilder.CreateType();
// Save the assembly so it can be examined with Ildasm.exe,
// or referenced by a test program.
myAsmBuilder.Save(myAsmName.Name + ".dll");
return retval;
}
public static void Main()
{
Type custDataType = BuildDynamicTypeWithProperties();
PropertyInfo[] custDataPropInfo = custDataType.GetProperties();
foreach (PropertyInfo pInfo in custDataPropInfo) {
Console.WriteLine("Property '{0}' created!", pInfo.ToString());
}
Console.WriteLine("---");
// Note that when invoking a property, you need to use the proper BindingFlags -
// BindingFlags.SetProperty when you invoke the "set" behavior, and
// BindingFlags.GetProperty when you invoke the "get" behavior. Also note that
// we invoke them based on the name we gave the property, as expected, and not
// the name of the methods we bound to the specific property behaviors.
object custData = Activator.CreateInstance(custDataType);
custDataType.InvokeMember("CustomerName", BindingFlags.SetProperty,
null, custData, new object[]{ "Joe User" });
Console.WriteLine("The customerName field of instance custData has been set to '{0}'.",
custDataType.InvokeMember("CustomerName", BindingFlags.GetProperty,
null, custData, new object[]{ }));
}
}
// --- O U T P U T ---
// The output should be as follows:
// -------------------
// Property 'System.String CustomerName [System.String]' created!
// ---
// The customerName field of instance custData has been set to 'Joe User'.
// -------------------
using namespace System;
using namespace System::Threading;
using namespace System::Reflection;
using namespace System::Reflection::Emit;
Type^ BuildDynamicTypeWithProperties()
{
AppDomain^ myDomain = Thread::GetDomain();
AssemblyName^ myAsmName = gcnew AssemblyName;
myAsmName->Name = "MyDynamicAssembly";
// To generate a persistable assembly, specify AssemblyBuilderAccess::RunAndSave.
AssemblyBuilder^ myAsmBuilder =
myDomain->DefineDynamicAssembly( myAsmName, AssemblyBuilderAccess::RunAndSave );
// Generate a persistable single-module assembly.
ModuleBuilder^ myModBuilder =
myAsmBuilder->DefineDynamicModule( myAsmName->Name, myAsmName->Name + ".dll" );
TypeBuilder^ myTypeBuilder = myModBuilder->DefineType( "CustomerData", TypeAttributes::Public );
// Define a private field to hold the property value.
FieldBuilder^ customerNameBldr = myTypeBuilder->DefineField( "customerName", String::typeid, FieldAttributes::Private );
// The last argument of DefineProperty is an empty array of Type
// objects, because the property has no parameters. (Alternatively,
// you can specify a null value.)
PropertyBuilder^ custNamePropBldr =
myTypeBuilder->DefineProperty( "CustomerName", PropertyAttributes::HasDefault, String::typeid, gcnew array<Type^>(0) );
// The property set and property get methods require a special
// set of attributes.
MethodAttributes getSetAttr =
MethodAttributes::Public | MethodAttributes::SpecialName |
MethodAttributes::HideBySig;
// Define the "get" accessor method for CustomerName.
MethodBuilder^ custNameGetPropMthdBldr =
myTypeBuilder->DefineMethod( "get_CustomerName",
getSetAttr,
String::typeid,
Type::EmptyTypes );
ILGenerator^ custNameGetIL = custNameGetPropMthdBldr->GetILGenerator();
custNameGetIL->Emit( OpCodes::Ldarg_0 );
custNameGetIL->Emit( OpCodes::Ldfld, customerNameBldr );
custNameGetIL->Emit( OpCodes::Ret );
// Define the "set" accessor method for CustomerName.
array<Type^>^temp2 = {String::typeid};
MethodBuilder^ custNameSetPropMthdBldr =
myTypeBuilder->DefineMethod( "set_CustomerName",
getSetAttr,
nullptr,
temp2 );
ILGenerator^ custNameSetIL = custNameSetPropMthdBldr->GetILGenerator();
custNameSetIL->Emit( OpCodes::Ldarg_0 );
custNameSetIL->Emit( OpCodes::Ldarg_1 );
custNameSetIL->Emit( OpCodes::Stfld, customerNameBldr );
custNameSetIL->Emit( OpCodes::Ret );
// Last, we must map the two methods created above to our PropertyBuilder to
// their corresponding behaviors, "get" and "set" respectively.
custNamePropBldr->SetGetMethod( custNameGetPropMthdBldr );
custNamePropBldr->SetSetMethod( custNameSetPropMthdBldr );
Type^ retval = myTypeBuilder->CreateType();
// Save the assembly so it can be examined with Ildasm.exe,
// or referenced by a test program.
myAsmBuilder->Save(myAsmName->Name + ".dll");
return retval;
}
int main()
{
Type^ custDataType = BuildDynamicTypeWithProperties();
array<PropertyInfo^>^custDataPropInfo = custDataType->GetProperties();
System::Collections::IEnumerator^ myEnum = custDataPropInfo->GetEnumerator();
while ( myEnum->MoveNext() )
{
PropertyInfo^ pInfo = safe_cast<PropertyInfo^>(myEnum->Current);
Console::WriteLine( "Property '{0}' created!", pInfo );
}
Console::WriteLine( "---" );
// Note that when invoking a property, you need to use the proper BindingFlags -
// BindingFlags::SetProperty when you invoke the "set" behavior, and
// BindingFlags::GetProperty when you invoke the "get" behavior. Also note that
// we invoke them based on the name we gave the property, as expected, and not
// the name of the methods we bound to the specific property behaviors.
Object^ custData = Activator::CreateInstance( custDataType );
array<Object^>^temp3 = {"Joe User"};
custDataType->InvokeMember( "CustomerName", BindingFlags::SetProperty, nullptr, custData, temp3 );
Console::WriteLine( "The customerName field of instance custData has been set to '{0}'.", custDataType->InvokeMember( "CustomerName", BindingFlags::GetProperty, nullptr, custData, gcnew array<Object^>(0) ) );
}
// --- O U T P U T ---
// The output should be as follows:
// -------------------
// Property 'System.String CustomerName [System.String]' created!
// ---
// The customerName field of instance custData has been set to 'Joe User'.
// -------------------
Vererbungshierarchie
System.Object
System.Reflection.MemberInfo
System.Reflection.PropertyInfo
System.Reflection.Emit.PropertyBuilder
Threadsicherheit
Alle öffentlichen statischen (Shared in Visual Basic) Member dieses Typs sind threadsicher. Bei Instanzmembern ist die Threadsicherheit nicht gewährleistet.
Plattformen
Windows 98, Windows 2000 SP4, Windows Millennium Edition, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
.NET Framework unterstützt nicht alle Versionen sämtlicher Plattformen. Eine Liste der unterstützten Versionen finden Sie unter Systemanforderungen.
Versionsinformationen
.NET Framework
Unterstützt in: 2.0, 1.1, 1.0