FieldBuilder Class

.NET Framework (current version)
 

Defines and represents a field. This class cannot be inherited.

Namespace:   System.Reflection.Emit
Assembly:  mscorlib (in mscorlib.dll)

System::Object
  System.Reflection::MemberInfo
    System.Reflection::FieldInfo
      System.Reflection.Emit::FieldBuilder

C#
C++
F#
VB
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[ClassInterfaceAttribute(ClassInterfaceType::None)]
[ComVisibleAttribute(true)]
[HostProtectionAttribute(SecurityAction::LinkDemand, MayLeakOnAbort = true)]
public ref class FieldBuilder sealed : FieldInfo, _FieldBuilder

NameDescription
System_CAPS_pubpropertyAttributes

Indicates the attributes of this field. This property is read-only.(Overrides FieldInfo::Attributes.)

System_CAPS_pubpropertyCustomAttributes

Gets a collection that contains this member's custom attributes.(Inherited from MemberInfo.)

System_CAPS_pubpropertyDeclaringType

Indicates a reference to the Type object for the type that declares this field. This property is read-only.(Overrides MemberInfo::DeclaringType.)

System_CAPS_pubpropertyFieldHandle

Indicates the internal metadata handle for this field. This property is read-only.(Overrides FieldInfo::FieldHandle.)

System_CAPS_pubpropertyFieldType

Indicates the Type object that represents the type of this field. This property is read-only.(Overrides FieldInfo::FieldType.)

System_CAPS_pubpropertyIsAssembly

Gets a value indicating whether the potential visibility of this field is described by FieldAttributes::Assembly; that is, the field is visible at most to other types in the same assembly, and is not visible to derived types outside the assembly.(Inherited from FieldInfo.)

System_CAPS_pubpropertyIsFamily

Gets a value indicating whether the visibility of this field is described by FieldAttributes::Family; that is, the field is visible only within its class and derived classes.(Inherited from FieldInfo.)

System_CAPS_pubpropertyIsFamilyAndAssembly

Gets a value indicating whether the visibility of this field is described by FieldAttributes::FamANDAssem; that is, the field can be accessed from derived classes, but only if they are in the same assembly.(Inherited from FieldInfo.)

System_CAPS_pubpropertyIsFamilyOrAssembly

Gets a value indicating whether the potential visibility of this field is described by FieldAttributes::FamORAssem; that is, the field can be accessed by derived classes wherever they are, and by classes in the same assembly.(Inherited from FieldInfo.)

System_CAPS_pubpropertyIsInitOnly

Gets a value indicating whether the field can only be set in the body of the constructor.(Inherited from FieldInfo.)

System_CAPS_pubpropertyIsLiteral

Gets a value indicating whether the value is written at compile time and cannot be changed.(Inherited from FieldInfo.)

System_CAPS_pubpropertyIsNotSerialized

Gets a value indicating whether this field has the NotSerialized attribute.(Inherited from FieldInfo.)

System_CAPS_pubpropertyIsPinvokeImpl

Gets a value indicating whether the corresponding PinvokeImpl attribute is set in FieldAttributes.(Inherited from FieldInfo.)

System_CAPS_pubpropertyIsPrivate

Gets a value indicating whether the field is private.(Inherited from FieldInfo.)

System_CAPS_pubpropertyIsPublic

Gets a value indicating whether the field is public.(Inherited from FieldInfo.)

System_CAPS_pubpropertyIsSecurityCritical

Gets a value that indicates whether the current field is security-critical or security-safe-critical at the current trust level. (Inherited from FieldInfo.)

System_CAPS_pubpropertyIsSecuritySafeCritical

Gets a value that indicates whether the current field is security-safe-critical at the current trust level. (Inherited from FieldInfo.)

System_CAPS_pubpropertyIsSecurityTransparent

Gets a value that indicates whether the current field is transparent at the current trust level.(Inherited from FieldInfo.)

System_CAPS_pubpropertyIsSpecialName

Gets a value indicating whether the corresponding SpecialName attribute is set in the FieldAttributes enumerator.(Inherited from FieldInfo.)

System_CAPS_pubpropertyIsStatic

Gets a value indicating whether the field is static.(Inherited from FieldInfo.)

System_CAPS_pubpropertyMemberType

Gets a MemberTypes value indicating that this member is a field.(Inherited from FieldInfo.)

System_CAPS_pubpropertyMetadataToken

Gets a value that identifies a metadata element.(Inherited from MemberInfo.)

System_CAPS_pubpropertyModule

Gets the module in which the type that contains this field is being defined.(Overrides MemberInfo::Module.)

System_CAPS_pubpropertyName

Indicates the name of this field. This property is read-only.(Overrides MemberInfo::Name.)

System_CAPS_pubpropertyReflectedType

Indicates the reference to the Type object from which this object was obtained. This property is read-only.(Overrides MemberInfo::ReflectedType.)

NameDescription
System_CAPS_pubmethodEquals(Object^)

Returns a value that indicates whether this instance is equal to a specified object.(Inherited from FieldInfo.)

System_CAPS_pubmethodGetCustomAttributes(Boolean)

Returns all the custom attributes defined for this field.(Overrides MemberInfo::GetCustomAttributes(Boolean).)

System_CAPS_pubmethodGetCustomAttributes(Type^, Boolean)

Returns all the custom attributes defined for this field identified by the given type.(Overrides MemberInfo::GetCustomAttributes(Type^, Boolean).)

System_CAPS_pubmethodGetCustomAttributesData()

Returns a list of CustomAttributeData objects representing data about the attributes that have been applied to the target member.(Inherited from MemberInfo.)

System_CAPS_pubmethodGetHashCode()

Returns the hash code for this instance.(Inherited from FieldInfo.)

System_CAPS_pubmethodGetOptionalCustomModifiers()

Gets an array of types that identify the optional custom modifiers of the field.(Inherited from FieldInfo.)

System_CAPS_pubmethodGetRawConstantValue()

Returns a literal value associated with the field by a compiler. (Inherited from FieldInfo.)

System_CAPS_pubmethodGetRequiredCustomModifiers()

Gets an array of types that identify the required custom modifiers of the property.(Inherited from FieldInfo.)

System_CAPS_pubmethodGetToken()

Returns the token representing this field.

System_CAPS_pubmethodGetType()

Gets the Type of the current instance.(Inherited from Object.)

System_CAPS_pubmethodGetValue(Object^)

Retrieves the value of the field supported by the given object.(Overrides FieldInfo::GetValue(Object^).)

System_CAPS_pubmethodGetValueDirect(TypedReference)

Returns the value of a field supported by a given object.(Inherited from FieldInfo.)

System_CAPS_pubmethodIsDefined(Type^, Boolean)

Indicates whether an attribute having the specified type is defined on a field.(Overrides MemberInfo::IsDefined(Type^, Boolean).)

System_CAPS_pubmethodSetConstant(Object^)

Sets the default value of this field.

System_CAPS_pubmethodSetCustomAttribute(ConstructorInfo^, array<Byte>^)

Sets a custom attribute using a specified custom attribute blob.

System_CAPS_pubmethodSetCustomAttribute(CustomAttributeBuilder^)

Sets a custom attribute using a custom attribute builder.

System_CAPS_pubmethodSetMarshal(UnmanagedMarshal^)

Obsolete. Describes the native marshaling of the field.

System_CAPS_pubmethodSetOffset(Int32)

Specifies the field layout.

System_CAPS_pubmethodSetValue(Object^, Object^)

Sets the value of the field supported by the given object.(Inherited from FieldInfo.)

System_CAPS_pubmethodSetValue(Object^, Object^, BindingFlags, Binder^, CultureInfo^)

Sets the value of the field supported by the given object.(Overrides FieldInfo::SetValue(Object^, Object^, BindingFlags, Binder^, CultureInfo^).)

System_CAPS_pubmethodSetValueDirect(TypedReference, Object^)

Sets the value of the field supported by the given object.(Inherited from FieldInfo.)

System_CAPS_pubmethodToString()

Returns a string that represents the current object.(Inherited from Object.)

NameDescription
System_CAPS_pubinterfaceSystem_CAPS_privmethod_FieldBuilder::GetIDsOfNames(Guid%, IntPtr, UInt32, UInt32, IntPtr)

Maps a set of names to a corresponding set of dispatch identifiers.

System_CAPS_pubinterfaceSystem_CAPS_privmethod_FieldBuilder::GetTypeInfo(UInt32, UInt32, IntPtr)

Retrieves the type information for an object, which can then be used to get the type information for an interface.

System_CAPS_pubinterfaceSystem_CAPS_privmethod_FieldBuilder::GetTypeInfoCount(UInt32%)

Retrieves the number of type information interfaces that an object provides (either 0 or 1).

System_CAPS_pubinterfaceSystem_CAPS_privmethod_FieldBuilder::Invoke(UInt32, Guid%, UInt32, Int16, IntPtr, IntPtr, IntPtr, IntPtr)

Provides access to properties and methods exposed by an object.

System_CAPS_pubinterfaceSystem_CAPS_privmethod_FieldInfo::GetIDsOfNames(Guid%, IntPtr, UInt32, UInt32, IntPtr)

Maps a set of names to a corresponding set of dispatch identifiers.(Inherited from FieldInfo.)

System_CAPS_pubinterfaceSystem_CAPS_privmethod_FieldInfo::GetType()

Gets a Type object representing the FieldInfo type.(Inherited from FieldInfo.)

System_CAPS_pubinterfaceSystem_CAPS_privmethod_FieldInfo::GetTypeInfo(UInt32, UInt32, IntPtr)

Retrieves the type information for an object, which can then be used to get the type information for an interface.(Inherited from FieldInfo.)

System_CAPS_pubinterfaceSystem_CAPS_privmethod_FieldInfo::GetTypeInfoCount(UInt32%)

Retrieves the number of type information interfaces that an object provides (either 0 or 1).(Inherited from FieldInfo.)

System_CAPS_pubinterfaceSystem_CAPS_privmethod_FieldInfo::Invoke(UInt32, Guid%, UInt32, Int16, IntPtr, IntPtr, IntPtr, IntPtr)

Provides access to properties and methods exposed by an object.(Inherited from FieldInfo.)

System_CAPS_pubinterfaceSystem_CAPS_privmethod_MemberInfo::GetIDsOfNames(Guid%, IntPtr, UInt32, UInt32, IntPtr)

Maps a set of names to a corresponding set of dispatch identifiers.(Inherited from MemberInfo.)

System_CAPS_pubinterfaceSystem_CAPS_privmethod_MemberInfo::GetType()

Gets a Type object representing the MemberInfo class.(Inherited from MemberInfo.)

System_CAPS_pubinterfaceSystem_CAPS_privmethod_MemberInfo::GetTypeInfo(UInt32, UInt32, IntPtr)

Retrieves the type information for an object, which can then be used to get the type information for an interface.(Inherited from MemberInfo.)

System_CAPS_pubinterfaceSystem_CAPS_privmethod_MemberInfo::GetTypeInfoCount(UInt32%)

Retrieves the number of type information interfaces that an object provides (either 0 or 1).(Inherited from MemberInfo.)

System_CAPS_pubinterfaceSystem_CAPS_privmethod_MemberInfo::Invoke(UInt32, Guid%, UInt32, Int16, IntPtr, IntPtr, IntPtr, IntPtr)

Provides access to properties and methods exposed by an object.(Inherited from MemberInfo.)

NameDescription
System_CAPS_pubmethodGetCustomAttribute(Type^)

Overloaded. Retrieves a custom attribute of a specified type that is applied to a specified member.(Defined by CustomAttributeExtensions.)

System_CAPS_pubmethodGetCustomAttribute(Type^, Boolean)

Overloaded. Retrieves a custom attribute of a specified type that is applied to a specified member, and optionally inspects the ancestors of that member.(Defined by CustomAttributeExtensions.)

System_CAPS_pubmethodGetCustomAttribute<T>()

Overloaded. Retrieves a custom attribute of a specified type that is applied to a specified member.(Defined by CustomAttributeExtensions.)

System_CAPS_pubmethodGetCustomAttribute<T>(Boolean)

Overloaded. Retrieves a custom attribute of a specified type that is applied to a specified member, and optionally inspects the ancestors of that member.(Defined by CustomAttributeExtensions.)

System_CAPS_pubmethodGetCustomAttributes()

Overloaded. Retrieves a collection of custom attributes that are applied to a specified member.(Defined by CustomAttributeExtensions.)

System_CAPS_pubmethodGetCustomAttributes(Type^)

Overloaded. Retrieves a collection of custom attributes of a specified type that are applied to a specified member.(Defined by CustomAttributeExtensions.)

System_CAPS_pubmethodGetCustomAttributes<T>(Boolean)

Overloaded. Retrieves a collection of custom attributes of a specified type that are applied to a specified member, and optionally inspects the ancestors of that member.(Defined by CustomAttributeExtensions.)

System_CAPS_pubmethodIsDefined(Type^)

Overloaded. Indicates whether custom attributes of a specified type are applied to a specified member.(Defined by CustomAttributeExtensions.)

Get an instance of FieldBuilder by calling DefineField, DefineInitializedData, or DefineUninitializedData.

System_CAPS_noteNote

The SetValue method is currently not supported. As a workaround, retrieve the FieldInfo by reflecting on the finished type and call SetValue to set the value of the field.

The following code sample illustrates the use of FieldBuilder.

C#
C++
VB
Copy 
using namespace System;
using namespace System::Threading;
using namespace System::Reflection;
using namespace System::Reflection::Emit;
Type^ CreateType( AppDomain^ currentDomain )
{
   // Create an assembly.
   AssemblyName^ myAssemblyName = gcnew AssemblyName;
   myAssemblyName->Name = "DynamicAssembly";
   AssemblyBuilder^ myAssembly = currentDomain->DefineDynamicAssembly( myAssemblyName, AssemblyBuilderAccess::Run );

   // Create a dynamic module in Dynamic Assembly.
   ModuleBuilder^ myModuleBuilder = myAssembly->DefineDynamicModule( "MyModule" );

   // Define a public class named S"MyClass" in the assembly.
   TypeBuilder^ myTypeBuilder = myModuleBuilder->DefineType( "MyClass", TypeAttributes::Public );

   // Define a private String field named S"MyField" in the type.
   FieldBuilder^ myFieldBuilder = myTypeBuilder->DefineField( "MyField", String::typeid, static_cast<FieldAttributes>(FieldAttributes::Private | FieldAttributes::Static) );

   // Create the constructor.
   array<Type^>^constructorArgs = {String::typeid};
   ConstructorBuilder^ constructor = myTypeBuilder->DefineConstructor( MethodAttributes::Public, CallingConventions::Standard, constructorArgs );
   ILGenerator^ constructorIL = constructor->GetILGenerator();
   constructorIL->Emit( OpCodes::Ldarg_0 );
   ConstructorInfo^ superConstructor = Object::typeid->GetConstructor( gcnew array<Type^>(0) );
   constructorIL->Emit( OpCodes::Call, superConstructor );
   constructorIL->Emit( OpCodes::Ldarg_0 );
   constructorIL->Emit( OpCodes::Ldarg_1 );
   constructorIL->Emit( OpCodes::Stfld, myFieldBuilder );
   constructorIL->Emit( OpCodes::Ret );

   // Create the MyMethod method.
   MethodBuilder^ myMethodBuilder = myTypeBuilder->DefineMethod( "MyMethod", MethodAttributes::Public, String::typeid, nullptr );
   ILGenerator^ methodIL = myMethodBuilder->GetILGenerator();
   methodIL->Emit( OpCodes::Ldarg_0 );
   methodIL->Emit( OpCodes::Ldfld, myFieldBuilder );
   methodIL->Emit( OpCodes::Ret );
   Console::WriteLine( "Name               : {0}", myFieldBuilder->Name );
   Console::WriteLine( "DeclaringType      : {0}", myFieldBuilder->DeclaringType );
   Console::WriteLine( "Type               : {0}", myFieldBuilder->FieldType );
   Console::WriteLine( "Token              : {0}", myFieldBuilder->GetToken().Token );
   return myTypeBuilder->CreateType();
}

int main()
{
   try
   {
      Type^ myType = CreateType( Thread::GetDomain() );

      // Create an instance of the S"HelloWorld" class.
      array<Object^>^type = {"HelloWorld"};
      Object^ helloWorld = Activator::CreateInstance( myType, type );

      // Invoke the S"MyMethod" method of the S"MyClass" class.
      Object^ myObject = myType->InvokeMember( "MyMethod", BindingFlags::InvokeMethod, nullptr, helloWorld, nullptr );
      Console::WriteLine( "MyClass::MyMethod returned: \"{0}\"", myObject );
   }
   catch ( Exception^ e ) 
   {
      Console::WriteLine( "Exception Caught {0}", e->Message );
   }
}

.NET Framework
Available since 1.1
Silverlight
Available since 2.0

Any public static ( Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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