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TypeBuilder Class

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Defines and creates new instances of classes during run time.

Inheritance Hierarchy

System.Object
  System.Reflection.MemberInfo
    System.Type
      System.Reflection.Emit.TypeBuilder

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

Syntax

'Declaration
<ClassInterfaceAttribute(ClassInterfaceType.None)> _
<ComVisibleAttribute(True)> _
Public NotInheritable Class TypeBuilder _
    Inherits Type

[ClassInterfaceAttribute(ClassInterfaceType.None)]
[ComVisibleAttribute(true)]
public sealed class TypeBuilder : Type

The TypeBuilder type exposes the following members.

Properties

  Name Description
Public property Assembly Gets the dynamic assembly that contains this type definition. (Overrides Type.Assembly.)
Public property AssemblyQualifiedName Gets the full name of this type, qualified by the display name of the assembly. (Overrides Type.AssemblyQualifiedName.)
Public property Attributes Gets the attributes associated with the Type. (Inherited from Type.)
Public property BaseType Gets the base type of this type. (Overrides Type.BaseType.)
Public property ContainsGenericParameters Gets a value indicating whether the current Type object has type parameters that have not been replaced by specific types. (Inherited from Type.)
Public property DeclaringMethod Gets the method that declared the current generic type parameter. (Overrides Type.DeclaringMethod.)
Public property DeclaringType Gets the type that declared this type. (Overrides Type.DeclaringType.)
Public property FullName Gets the full path of this type. (Overrides Type.FullName.)
Public property GenericParameterAttributes Gets a value that indicates the covariance and special constraints of the current generic type parameter. (Overrides Type.GenericParameterAttributes.)
Public property GenericParameterPosition Gets the position of a type parameter in the type parameter list of the generic type that declared the parameter. (Overrides Type.GenericParameterPosition.)
Public property GUID Gets the GUID of this type. (Overrides Type.GUID.)
Public property HasElementType Gets a value indicating whether the current Type encompasses or refers to another type; that is, whether the current Type is an array, a pointer, or is passed by reference. (Inherited from Type.)
Public property IsAbstract Gets a value indicating whether the Type is abstract and must be overridden. (Inherited from Type.)
Public property IsAnsiClass Gets a value indicating whether the string format attribute AnsiClass is selected for the Type. (Inherited from Type.)
Public property IsArray Gets a value indicating whether the Type is an array. (Inherited from Type.)
Public property IsAutoClass Gets a value indicating whether the string format attribute AutoClass is selected for the Type. (Inherited from Type.)
Public property IsAutoLayout Gets a value indicating whether the class layout attribute AutoLayout is selected for the Type. (Inherited from Type.)
Public property IsByRef Gets a value indicating whether the Type is passed by reference. (Inherited from Type.)
Public property IsClass Gets a value indicating whether the Type is a class; that is, not a value type or interface. (Inherited from Type.)
Public property IsCOMObject Gets a value indicating whether the Type is a COM object. (Inherited from Type.)
Public property IsEnum Gets a value indicating whether the current Type represents an enumeration. (Inherited from Type.)
Public property IsGenericParameter Gets a value indicating whether the current type is a generic type parameter. (Overrides Type.IsGenericParameter.)
Public property IsGenericType Gets a value indicating whether the current type is a generic type. (Overrides Type.IsGenericType.)
Public property IsGenericTypeDefinition Gets a value indicating whether the current TypeBuilder represents a generic type definition from which other generic types can be constructed. (Overrides Type.IsGenericTypeDefinition.)
Public property IsImport Gets a value indicating whether the Type has a ComImportAttribute attribute applied, indicating that it was imported from a COM type library. (Inherited from Type.)
Public property IsInterface Gets a value indicating whether the Type is an interface; that is, not a class or a value type. (Inherited from Type.)
Public property IsNested Gets a value indicating whether the current Type object represents a type whose definition is nested inside the definition of another type. (Inherited from Type.)
Public property IsNestedAssembly Gets a value indicating whether the Type is nested and visible only within its own assembly. (Inherited from Type.)
Public property IsNestedFamANDAssem Gets a value indicating whether the Type is nested and visible only to classes that belong to both its own family and its own assembly. (Inherited from Type.)
Public property IsNestedFamily Gets a value indicating whether the Type is nested and visible only within its own family. (Inherited from Type.)
Public property IsNestedFamORAssem Gets a value indicating whether the Type is nested and visible only to classes that belong to either its own family or to its own assembly. (Inherited from Type.)
Public property IsNestedPrivate Gets a value indicating whether the Type is nested and declared private. (Inherited from Type.)
Public property IsNestedPublic Gets a value indicating whether a class is nested and declared public. (Inherited from Type.)
Public property IsNotPublic Gets a value indicating whether the Type is not declared public. (Inherited from Type.)
Public property IsPointer Gets a value indicating whether the Type is a pointer. (Inherited from Type.)
Public property IsPrimitive Gets a value indicating whether the Type is one of the primitive types. (Inherited from Type.)
Public property IsPublic Gets a value indicating whether the Type is declared public. (Inherited from Type.)
Public property IsSealed Gets a value indicating whether the Type is declared sealed. (Inherited from Type.)
Public property IsSpecialName Gets a value indicating whether the Type has a name that requires special handling. (Inherited from Type.)
Public property IsUnicodeClass Gets a value indicating whether the string format attribute UnicodeClass is selected for the Type. (Inherited from Type.)
Public property IsValueType Gets a value indicating whether the Type is a value type. (Inherited from Type.)
Public property IsVisible Gets a value indicating whether the Type can be accessed by code outside the assembly. (Inherited from Type.)
Public property MemberType Gets a MemberTypes value indicating that this member is a type or a nested type. (Inherited from Type.)
Public property MetadataToken Gets a value that identifies a metadata element. (Inherited from MemberInfo.)
Public property Module Gets the dynamic module that contains this type definition. (Overrides Type.Module.)
Public property Name Gets the name of this type. (Overrides MemberInfo.Name.)
Public property Namespace Gets the namespace where this TypeBuilder is defined. (Overrides Type.Namespace.)
Public property PackingSize Gets the packing size of this type.
Public property ReflectedType Gets the type that was used to obtain this type. (Overrides Type.ReflectedType.)
Public property Size Gets the total size of a type.
Public property TypeHandle Not supported in dynamic modules. (Overrides Type.TypeHandle.)
Public property TypeToken Gets the type token of this type.
Public property UnderlyingSystemType Gets the underlying system type for this TypeBuilder. (Overrides Type.UnderlyingSystemType.)

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Methods

  Name Description
Public method AddInterfaceImplementation Adds an interface that this type implements.
Public method CreateType Creates a Type object for the class. After defining fields and methods on the class, CreateType is called in order to load its Type object.
Public method DefineConstructor(MethodAttributes, CallingConventions, array<Type[]) Adds a new constructor to the type, with the given attributes and signature.
Public method DefineConstructor(MethodAttributes, CallingConventions, array<Type[], array<array<Type[][], array<array<Type[][]) Adds a new constructor to the type, with the given attributes, signature, and custom modifiers.
Public method DefineDefaultConstructor Defines the default constructor. The constructor defined here will simply call the default constructor of the parent.
Public method DefineEvent Adds a new event to the type, with the given name, attributes and event type.
Public method DefineField(String, Type, FieldAttributes) Adds a new field to the type, with the given name, attributes, and field type.
Public method DefineField(String, Type, array<Type[], array<Type[], FieldAttributes) Adds a new field to the type, with the given name, attributes, field type, and custom modifiers.
Public method DefineGenericParameters Defines the generic type parameters for the current type, specifying their number and their names, and returns an array of GenericTypeParameterBuilder objects that can be used to set their constraints.
Public method DefineMethod(String, MethodAttributes) Adds a new method to the type, with the specified name and method attributes.
Public method DefineMethod(String, MethodAttributes, CallingConventions) Adds a new method to the type, with the specified name, method attributes, and calling convention.
Public method DefineMethod(String, MethodAttributes, Type, array<Type[]) Adds a new method to the type, with the specified name, method attributes, and method signature.
Public method DefineMethod(String, MethodAttributes, CallingConventions, Type, array<Type[]) Adds a new method to the type, with the specified name, method attributes, calling convention, and method signature.
Public method DefineMethod(String, MethodAttributes, CallingConventions, Type, array<Type[], array<Type[], array<Type[], array<array<Type[][], array<array<Type[][]) Adds a new method to the type, with the specified name, method attributes, calling convention, method signature, and custom modifiers.
Public method DefineMethodOverride Specifies a given method body that implements a given method declaration, potentially with a different name.
Public method DefineNestedType(String) Defines a nested type, given its name.
Public method DefineNestedType(String, TypeAttributes) Defines a nested type, given its name and attributes.
Public method DefineNestedType(String, TypeAttributes, Type) Defines a nested type, given its name, attributes, and the type that it extends.
Public method DefineNestedType(String, TypeAttributes, Type, array<Type[]) Defines a nested type, given its name, attributes, the type that it extends, and the interfaces that it implements.
Public method DefineProperty(String, PropertyAttributes, Type, array<Type[]) Adds a new property to the type, with the given name and property signature.
Public method DefineProperty(String, PropertyAttributes, CallingConventions, Type, array<Type[]) Adds a new property to the type, with the given name, attributes, calling convention, and property signature.
Public method DefineProperty(String, PropertyAttributes, Type, array<Type[], array<Type[], array<Type[], array<array<Type[][], array<array<Type[][]) Adds a new property to the type, with the given name, property signature, and custom modifiers.
Public method DefineProperty(String, PropertyAttributes, CallingConventions, Type, array<Type[], array<Type[], array<Type[], array<array<Type[][], array<array<Type[][]) Adds a new property to the type, with the given name, calling convention, property signature, and custom modifiers.
Public method DefineTypeInitializer Defines the initializer for this type.
Public method Equals(Object) Determines if the underlying system type of the current Type is the same as the underlying system type of the specified Object. (Inherited from Type.)
Public method Equals(Type) Determines if the underlying system type of the current Type is the same as the underlying system type of the specified Type. (Inherited from Type.)
Protected method Finalize Allows an object to try to free resources and perform other cleanup operations before the Object is reclaimed by garbage collection. (Inherited from Object.)
Public method FindMembers Returns a filtered array of MemberInfo objects of the specified member type. (Inherited from Type.)
Public method GetArrayRank Gets the number of dimensions in an Array. (Inherited from Type.)
Protected method GetAttributeFlagsImpl When overridden in a derived class, implements the Attributes property and gets a bitmask indicating the attributes associated with the Type. (Inherited from Type.)
Public method GetConstructor(array<Type[]) Searches for a public instance constructor whose parameters match the types in the specified array. (Inherited from Type.)
Public methodStatic member GetConstructor(Type, ConstructorInfo) Returns the constructor of the specified constructed generic type that corresponds to the specified constructor of the generic type definition.
Public method GetConstructor(BindingFlags, Binder, array<Type[], array<ParameterModifier[]) Searches for a constructor whose parameters match the specified argument types and modifiers, using the specified binding constraints. (Inherited from Type.)
Protected method GetConstructorImpl When overridden in a derived class, searches for a constructor whose parameters match the specified argument types and modifiers, using the specified binding constraints and the specified calling convention. (Inherited from Type.)
Public method GetConstructors() Returns all the public constructors defined for the current Type. (Inherited from Type.)
Public method GetConstructors(BindingFlags) Returns an array of ConstructorInfo objects representing the public and non-public constructors defined for this class, as specified. (Overrides Type.GetConstructors(BindingFlags).)
Public method GetCustomAttributes(Boolean) Returns all the custom attributes defined for this type. (Overrides MemberInfo.GetCustomAttributes(Boolean).)
Public method GetCustomAttributes(Type, Boolean) Returns all the custom attributes of the current type that are assignable to a specified type. (Overrides MemberInfo.GetCustomAttributes(Type, Boolean).)
Public method GetDefaultMembers Searches for the members defined for the current Type whose DefaultMemberAttribute is set. (Inherited from Type.)
Public method GetElementType Calling this method always throws NotSupportedException. (Overrides Type.GetElementType().)
Public method GetEvent(String) Returns the EventInfo object representing the specified public event. (Inherited from Type.)
Public method GetEvent(String, BindingFlags) Returns the event with the specified name. (Overrides Type.GetEvent(String, BindingFlags).)
Public method GetEvents() Returns the public events declared or inherited by this type. (Overrides Type.GetEvents().)
Public method GetEvents(BindingFlags) Returns the public and non-public events that are declared by this type. (Overrides Type.GetEvents(BindingFlags).)
Public method GetField(String) Searches for the public field with the specified name. (Inherited from Type.)
Public method GetField(String, BindingFlags) Returns the field specified by the given name. (Overrides Type.GetField(String, BindingFlags).)
Public methodStatic member GetField(Type, FieldInfo) Returns the field of the specified constructed generic type that corresponds to the specified field of the generic type definition.
Public method GetFields() Returns all the public fields of the current Type. (Inherited from Type.)
Public method GetFields(BindingFlags) Returns the public and non-public fields that are declared by this type. (Overrides Type.GetFields(BindingFlags).)
Public method GetGenericArguments Returns an array of Type objects representing the type arguments of a generic type or the type parameters of a generic type definition. (Overrides Type.GetGenericArguments().)
Public method GetGenericParameterConstraints Returns an array of Type objects that represent the constraints on the current generic type parameter. (Inherited from Type.)
Public method GetGenericTypeDefinition Returns a Type object that represents a generic type definition from which the current type can be obtained. (Overrides Type.GetGenericTypeDefinition().)
Public method GetHashCode Returns the hash code for this instance. (Inherited from Type.)
Public method GetInterface Returns the interface implemented (directly or indirectly) by this class with the fully qualified name matching the given interface name. (Overrides Type.GetInterface(String, Boolean).)
Public method GetInterfaceMap Returns an interface mapping for the requested interface. (Overrides Type.GetInterfaceMap(Type).)
Public method GetInterfaces Returns an array of all the interfaces implemented on this type and its base types. (Overrides Type.GetInterfaces().)
Public method GetMember(String) Searches for the public members with the specified name. (Inherited from Type.)
Public method GetMember(String, BindingFlags) Searches for the specified members, using the specified binding constraints. (Inherited from Type.)
Public method GetMember(String, MemberTypes, BindingFlags) Returns all the public and non-public members declared or inherited by this type, as specified. (Overrides Type.GetMember(String, MemberTypes, BindingFlags).)
Public method GetMembers() Returns all the public members of the current Type. (Inherited from Type.)
Public method GetMembers(BindingFlags) Returns the members for the public and non-public members declared or inherited by this type. (Overrides Type.GetMembers(BindingFlags).)
Public method GetMethod(String) Searches for the public method with the specified name. (Inherited from Type.)
Public method GetMethod(String, BindingFlags) Searches for the specified method, using the specified binding constraints. (Inherited from Type.)
Public method GetMethod(String, array<Type[]) Searches for the specified public method whose parameters match the specified argument types. (Inherited from Type.)
Public methodStatic member GetMethod(Type, MethodInfo) Returns the method of the specified constructed generic type that corresponds to the specified method of the generic type definition.
Public method GetMethod(String, array<Type[], array<ParameterModifier[]) Searches for the specified public method whose parameters match the specified argument types and modifiers. (Inherited from Type.)
Public method GetMethod(String, BindingFlags, Binder, array<Type[], array<ParameterModifier[]) Searches for the specified method whose parameters match the specified argument types and modifiers, using the specified binding constraints. (Inherited from Type.)
Public method GetMethod(String, BindingFlags, Binder, CallingConventions, array<Type[], array<ParameterModifier[]) Searches for the specified method whose parameters match the specified argument types and modifiers, using the specified binding constraints and the specified calling convention. (Inherited from Type.)
Protected method GetMethodImpl When overridden in a derived class, searches for the specified method whose parameters match the specified argument types and modifiers, using the specified binding constraints and the specified calling convention. (Inherited from Type.)
Public method GetMethods() Returns all the public methods of the current Type. (Inherited from Type.)
Public method GetMethods(BindingFlags) Returns all the public and non-public methods declared or inherited by this type, as specified. (Overrides Type.GetMethods(BindingFlags).)
Public method GetNestedType Returns the public and non-public nested types that are declared by this type. (Overrides Type.GetNestedType(String, BindingFlags).)
Public method GetNestedTypes Returns the public and non-public nested types that are declared or inherited by this type. (Overrides Type.GetNestedTypes(BindingFlags).)
Public method GetProperties() Returns all the public properties of the current Type. (Inherited from Type.)
Public method GetProperties(BindingFlags) Returns all the public and non-public properties declared or inherited by this type, as specified. (Overrides Type.GetProperties(BindingFlags).)
Public method GetProperty(String) Searches for the public property with the specified name. (Inherited from Type.)
Public method GetProperty(String, BindingFlags) Searches for the specified property, using the specified binding constraints. (Inherited from Type.)
Public method GetProperty(String, Type) Searches for the public property with the specified name and return type. (Inherited from Type.)
Public method GetProperty(String, Type, array<Type[]) Searches for the specified public property whose parameters match the specified argument types. (Inherited from Type.)
Public method GetProperty(String, Type, array<Type[], array<ParameterModifier[]) Searches for the specified public property whose parameters match the specified argument types and modifiers. (Inherited from Type.)
Public method GetProperty(String, BindingFlags, Binder, Type, array<Type[], array<ParameterModifier[]) Searches for the specified property whose parameters match the specified argument types and modifiers, using the specified binding constraints. (Inherited from Type.)
Protected method GetPropertyImpl When overridden in a derived class, searches for the specified property whose parameters match the specified argument types and modifiers, using the specified binding constraints. (Inherited from Type.)
Public method GetType() Gets the current Type. (Inherited from Type.)
Protected method HasElementTypeImpl When overridden in a derived class, implements the HasElementType property and determines whether the current Type encompasses or refers to another type; that is, whether the current Type is an array, a pointer, or is passed by reference. (Inherited from Type.)
Public method InvokeMember(String, BindingFlags, Binder, Object, array<Object[]) Invokes the specified member, using the specified binding constraints and matching the specified argument list. (Inherited from Type.)
Public method InvokeMember(String, BindingFlags, Binder, Object, array<Object[], array<ParameterModifier[], CultureInfo, array<String[]) Invokes the specified member. The method that is to be invoked must be accessible and provide the most specific match with the specified argument list, under the constraints of the specified binder and invocation attributes. (Overrides Type.InvokeMember(String, BindingFlags, Binder, Object, array<Object[], array<ParameterModifier[], CultureInfo, array<String[]).)
Protected method IsArrayImpl When overridden in a derived class, implements the IsArray property and determines whether the Type is an array. (Inherited from Type.)
Public method IsAssignableFrom Determines whether an instance of the current Type can be assigned from an instance of the specified Type. (Overrides Type.IsAssignableFrom(Type).)
Protected method IsByRefImpl When overridden in a derived class, implements the IsByRef property and determines whether the Type is passed by reference. (Inherited from Type.)
Protected method IsCOMObjectImpl When overridden in a derived class, implements the IsCOMObject property and determines whether the Type is a COM object. (Inherited from Type.)
Public method IsCreated Returns a value that indicates whether the current dynamic type has been created.
Public method IsDefined Determines whether a custom attribute is applied to the current type. (Overrides MemberInfo.IsDefined(Type, Boolean).)
Public method IsInstanceOfType Determines whether the specified object is an instance of the current Type. (Inherited from Type.)
Protected method IsPointerImpl When overridden in a derived class, implements the IsPointer property and determines whether the Type is a pointer. (Inherited from Type.)
Protected method IsPrimitiveImpl When overridden in a derived class, implements the IsPrimitive property and determines whether the Type is one of the primitive types. (Inherited from Type.)
Public method IsSubclassOf Determines whether this type is derived from a specified type. (Overrides Type.IsSubclassOf(Type).)
Protected method IsValueTypeImpl Implements the IsValueType property and determines whether the Type is a value type; that is, not a class or an interface. (Inherited from Type.)
Public method MakeArrayType() Returns a Type object that represents a one-dimensional array of the current type, with a lower bound of zero. (Overrides Type.MakeArrayType().)
Public method MakeArrayType(Int32) Returns a Type object that represents an array of the current type, with the specified number of dimensions. (Overrides Type.MakeArrayType(Int32).)
Public method MakeByRefType Returns a Type object that represents the current type when passed as a ref parameter (ByRef in Visual Basic). (Overrides Type.MakeByRefType().)
Public method MakeGenericType Substitutes the elements of an array of types for the type parameters of the current generic type definition, and returns the resulting constructed type. (Overrides Type.MakeGenericType(array<Type[]).)
Public method MakePointerType Returns a Type object that represents the type of an unmanaged pointer to the current type. (Overrides Type.MakePointerType().)
Protected method MemberwiseClone Creates a shallow copy of the current Object. (Inherited from Object.)
Public method SetCustomAttribute Set a custom attribute using a custom attribute builder.
Public method SetParent Sets the base type of the type currently under construction.
Public method ToString Returns the name of the type, excluding the namespace. (Overrides Type.ToString().)

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Fields

  Name Description
Public fieldStatic member UnspecifiedTypeSize Represents that total size for the type is not specified.

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Remarks

TypeBuilder is the root class used to control the creation of dynamic classes in the runtime. TypeBuilder provides a set of routines that are used to define classes, add methods and fields, and create the class inside the runtime. A new TypeBuilder can be created from a dynamic module.

To create an array type, pointer type, or byref type for an incomplete type that is represented by a TypeBuilder object, use the MakeArrayType method, MakePointerType method, or MakeByRefType method, respectively.

Examples

The following code example shows how to define a dynamic assembly with one module. The module in the example assembly contains one type, MyDynamicType, which has a private field, a property that gets and sets the private field, constructors that initialize the private field, and a method that multiplies a user-supplied number by the private field value and returns the result.

NoteNote:

To run this example, see Building Examples That Use a Demo Method and a TextBlock Control.

 
Imports System.Reflection
Imports System.Reflection.Emit

Class Example

   Public Shared Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)

      ' In this version of the runtime, an assembly consists of one 
      ' module which contains zero or more types. This example 
      ' creates an assembly containing one public type named
      ' "MyDynamicType". The type has a private field, a property 
      ' that gets and sets the private field, constructors that 
      ' initialize the private field, and a method that multiplies
      ' a user-supplied number by the private field value and returns 
      ' the result. The code might look like this in Visual Basic:
      '
      'Public Class MyDynamicType
      '    Private m_number As Integer
      '
      '    Public Sub New()
      '        Me.New(42)
      '    End Sub
      '    Public Sub New(ByVal initNumber As Integer)
      '        m_number = initNumber
      '    End Sub
      '    Public Property Number As Integer
      '        Get
      '            Return m_number
      '        End Get
      '        Set
      '            m_Number = Value
      '        End Set
      '    End Property
      '
      '    Public Function MyMethod(ByVal multiplier As Integer) As Integer
      '        Return m_Number * multiplier
      '    End Function

      Dim aName As New AssemblyName("DynamicAssemblyExample")
      Dim ab As AssemblyBuilder = _
          AppDomain.CurrentDomain.DefineDynamicAssembly( _
              aName, _
              AssemblyBuilderAccess.Run)

      ' Create the module.
      Dim mb As ModuleBuilder = ab.DefineDynamicModule(aName.Name)

      Dim tb As TypeBuilder = _
          mb.DefineType("MyDynamicType", TypeAttributes.Public)

      ' Add a private field of type Integer (Int32).
      Dim fbNumber As FieldBuilder = tb.DefineField( _
          "m_number", _
          GetType(Integer), _
          FieldAttributes.Private)

      ' Define a constructor that takes an integer argument and 
      ' stores it in the private field. 
      Dim parameterTypes() As Type = {GetType(Integer)}
      Dim ctor1 As ConstructorBuilder = _
          tb.DefineConstructor( _
              MethodAttributes.Public, _
              CallingConventions.Standard, _
              parameterTypes)

      Dim ctor1IL As ILGenerator = ctor1.GetILGenerator()
      ' For a constructor, argument zero is a reference to the new
      ' instance. Push it on the stack before calling the base
      ' class constructor. Specify the default constructor of the 
      ' base class (System.Object) by passing an empty array of 
      ' types (Type.EmptyTypes) to GetConstructor.
      ctor1IL.Emit(OpCodes.Ldarg_0)
      ctor1IL.Emit(OpCodes.Call, _
          GetType(Object).GetConstructor(Type.EmptyTypes))
      ' Push the instance on the stack before pushing the argument
      ' that is to be assigned to the private field m_number.
      ctor1IL.Emit(OpCodes.Ldarg_0)
      ctor1IL.Emit(OpCodes.Ldarg_1)
      ctor1IL.Emit(OpCodes.Stfld, fbNumber)
      ctor1IL.Emit(OpCodes.Ret)

      ' Define a default constructor that supplies a default value
      ' for the private field. For parameter types, pass the empty
      ' array of types or pass Nothing.
      Dim ctor0 As ConstructorBuilder = tb.DefineConstructor( _
          MethodAttributes.Public, _
          CallingConventions.Standard, _
          Type.EmptyTypes)

      Dim ctor0IL As ILGenerator = ctor0.GetILGenerator()
      ' For a constructor, argument zero is a reference to the new
      ' instance. Push it on the stack before pushing the default
      ' value on the stack, then call constructor ctor1.
      ctor0IL.Emit(OpCodes.Ldarg_0)
      ctor0IL.Emit(OpCodes.Ldc_I4_S, 42)
      ctor0IL.Emit(OpCodes.Call, ctor1)
      ctor0IL.Emit(OpCodes.Ret)

      ' Define a property named Number that gets and sets the private 
      ' field.
      '
      ' 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 the built-in array with no elements: Type.EmptyTypes)
      Dim pbNumber As PropertyBuilder = tb.DefineProperty( _
          "Number", _
          PropertyAttributes.HasDefault, _
          GetType(Integer), _
          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 Number. The method returns
      ' an integer and has no arguments. (Note that Nothing could be 
      ' used instead of Types.EmptyTypes)
      Dim mbNumberGetAccessor As MethodBuilder = tb.DefineMethod( _
          "get_Number", _
          getSetAttr, _
          GetType(Integer), _
          Type.EmptyTypes)

      Dim numberGetIL As ILGenerator = mbNumberGetAccessor.GetILGenerator()
      ' For an instance property, argument zero is the instance. Load the 
      ' instance, then load the private field and return, leaving the
      ' field value on the stack.
      numberGetIL.Emit(OpCodes.Ldarg_0)
      numberGetIL.Emit(OpCodes.Ldfld, fbNumber)
      numberGetIL.Emit(OpCodes.Ret)

      ' Define the "set" accessor method for Number, which has no return
      ' type and takes one argument of type Integer (Int32).
      Dim mbNumberSetAccessor As MethodBuilder = _
          tb.DefineMethod( _
              "set_Number", _
              getSetAttr, _
              Nothing, _
              New Type() {GetType(Integer)})

      Dim numberSetIL As ILGenerator = mbNumberSetAccessor.GetILGenerator()
      ' Load the instance and then the numeric argument, then store the
      ' argument in the field.
      numberSetIL.Emit(OpCodes.Ldarg_0)
      numberSetIL.Emit(OpCodes.Ldarg_1)
      numberSetIL.Emit(OpCodes.Stfld, fbNumber)
      numberSetIL.Emit(OpCodes.Ret)

      ' Last, map the "get" and "set" accessor methods to the 
      ' PropertyBuilder. The property is now complete. 
      pbNumber.SetGetMethod(mbNumberGetAccessor)
      pbNumber.SetSetMethod(mbNumberSetAccessor)

      ' Define a method that accepts an integer argument and returns
      ' the product of that integer and the private field m_number. This
      ' time, the array of parameter types is created on the fly.
      Dim meth As MethodBuilder = tb.DefineMethod( _
          "MyMethod", _
          MethodAttributes.Public, _
          GetType(Integer), _
          New Type() {GetType(Integer)})

      Dim methIL As ILGenerator = meth.GetILGenerator()
      ' To retrieve the private instance field, load the instance it
      ' belongs to (argument zero). After loading the field, load the 
      ' argument one and then multiply. Return from the method with 
      ' the return value (the product of the two numbers) on the 
      ' execution stack.
      methIL.Emit(OpCodes.Ldarg_0)
      methIL.Emit(OpCodes.Ldfld, fbNumber)
      methIL.Emit(OpCodes.Ldarg_1)
      methIL.Emit(OpCodes.Mul)
      methIL.Emit(OpCodes.Ret)

      ' Finish the type.
      Dim t As Type = tb.CreateType()

      ' The code can be executed immediately. Start by getting reflection
      ' objects for the method and the property.
      Dim mi As MethodInfo = t.GetMethod("MyMethod")
      Dim pi As PropertyInfo = t.GetProperty("Number")

      ' Create an instance of MyDynamicType using the default 
      ' constructor. 
      Dim o1 As Object = Activator.CreateInstance(t)

      ' Display the value of the property, then change it to 127 and 
      ' display it again. Use Nothing to indicate that the property
      ' has no index.
      outputBlock.Text += String.Format("o1.Number: {0}" & vbCrLf, _
          pi.GetValue(o1, Nothing)) 
      pi.SetValue(o1, 127, Nothing)
      outputBlock.Text += String.Format("o1.Number: {0}" & vbCrLf, _
          pi.GetValue(o1, Nothing)) 

      ' Call MyMethod, passing 22, and display the return value, 22
      ' times 127. Arguments must be passed as an array, even when
      ' there is only one.
      Dim arguments() As Object = {22}
      outputBlock.Text &= String.Format("o1.MyMethod(22): {0}" & vbCrLf, _
          mi.Invoke(o1, arguments))

      ' Create an instance of MyDynamicType using the constructor
      ' that specifies m_Number. The constructor is identified by
      ' matching the types in the argument array. In this case, 
      ' the argument array is created on the fly. Display the 
      ' property value.
      Dim o2 As Object = Activator.CreateInstance(t, _
          New Object() {5280})
      outputBlock.Text += String.Format("o2.Number: {0}" & vbCrLf, _
          pi.GetValue(o2, Nothing))

   End Sub
End Class

' This code produces the following output:
'
'o1.Number: 42
'o1.Number: 127
'o1.MyMethod(22): 2794
'o2.Number: 5280

using System;
using System.Reflection;
using System.Reflection.Emit;

class Example
{
   public static void Demo(System.Windows.Controls.TextBlock outputBlock)
   {
      // In this version of the runtime, an assembly consists of one 
      // module which contains zero or more types. This example 
      // creates an assembly containing one public type named
      // "MyDynamicType". The type has a private field, a property 
      // that gets and sets the private field, constructors that 
      // initialize the private field, and a method that multiplies 
      // a user-supplied number by the private field value and returns
      // the result. In C# the type might look like this:
      /*
      public class MyDynamicType
      {
          private int m_number;

          public MyDynamicType() : this(42) {}
          public MyDynamicType(int initNumber)
          {
              m_number = initNumber;
          }

          public int Number
          {
              get { return m_number; }
              set { m_number = value; }
          }

          public int MyMethod(int multiplier)
          {
              return m_number * multiplier;
          }
      }
      */

      AssemblyName aName = new AssemblyName("DynamicAssemblyExample");
      AssemblyBuilder ab =
          AppDomain.CurrentDomain.DefineDynamicAssembly(
              aName,
              AssemblyBuilderAccess.Run);

      // Create the module.
      ModuleBuilder mb = ab.DefineDynamicModule(aName.Name);

      TypeBuilder tb = mb.DefineType(
          "MyDynamicType",
           TypeAttributes.Public);

      // Add a private field of type int (Int32).
      FieldBuilder fbNumber = tb.DefineField(
          "m_number",
          typeof(int),
          FieldAttributes.Private);

      // Define a constructor that takes an integer argument and 
      // stores it in the private field. 
      Type[] parameterTypes = { typeof(int) };
      ConstructorBuilder ctor1 = tb.DefineConstructor(
          MethodAttributes.Public,
          CallingConventions.Standard,
          parameterTypes);

      ILGenerator ctor1IL = ctor1.GetILGenerator();
      // For a constructor, argument zero is a reference to the new
      // instance. Push it on the stack before calling the base
      // class constructor. Specify the default constructor of the 
      // base class (System.Object) by passing an empty array of 
      // types (Type.EmptyTypes) to GetConstructor.
      ctor1IL.Emit(OpCodes.Ldarg_0);
      ctor1IL.Emit(OpCodes.Call,
          typeof(object).GetConstructor(Type.EmptyTypes));
      // Push the instance on the stack before pushing the argument
      // that is to be assigned to the private field m_number.
      ctor1IL.Emit(OpCodes.Ldarg_0);
      ctor1IL.Emit(OpCodes.Ldarg_1);
      ctor1IL.Emit(OpCodes.Stfld, fbNumber);
      ctor1IL.Emit(OpCodes.Ret);

      // Define a default constructor that supplies a default value
      // for the private field. For parameter types, pass the empty
      // array of types or pass null.
      ConstructorBuilder ctor0 = tb.DefineConstructor(
          MethodAttributes.Public,
          CallingConventions.Standard,
          Type.EmptyTypes);

      ILGenerator ctor0IL = ctor0.GetILGenerator();
      // For a constructor, argument zero is a reference to the new
      // instance. Push it on the stack before pushing the default
      // value on the stack, then call constructor ctor1.
      ctor0IL.Emit(OpCodes.Ldarg_0);
      ctor0IL.Emit(OpCodes.Ldc_I4_S, 42);
      ctor0IL.Emit(OpCodes.Call, ctor1);
      ctor0IL.Emit(OpCodes.Ret);

      // Define a property named Number that gets and sets the private 
      // field.
      //
      // 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 the built-in array with no elements: Type.EmptyTypes)
      PropertyBuilder pbNumber = tb.DefineProperty(
          "Number",
          PropertyAttributes.HasDefault,
          typeof(int),
          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 Number. The method returns
      // an integer and has no arguments. (Note that null could be 
      // used instead of Types.EmptyTypes)
      MethodBuilder mbNumberGetAccessor = tb.DefineMethod(
          "get_Number",
          getSetAttr,
          typeof(int),
          Type.EmptyTypes);

      ILGenerator numberGetIL = mbNumberGetAccessor.GetILGenerator();
      // For an instance property, argument zero is the instance. Load the 
      // instance, then load the private field and return, leaving the
      // field value on the stack.
      numberGetIL.Emit(OpCodes.Ldarg_0);
      numberGetIL.Emit(OpCodes.Ldfld, fbNumber);
      numberGetIL.Emit(OpCodes.Ret);

      // Define the "set" accessor method for Number, which has no return
      // type and takes one argument of type int (Int32).
      MethodBuilder mbNumberSetAccessor = tb.DefineMethod(
          "set_Number",
          getSetAttr,
          null,
          new Type[] { typeof(int) });

      ILGenerator numberSetIL = mbNumberSetAccessor.GetILGenerator();
      // Load the instance and then the numeric argument, then store the
      // argument in the field.
      numberSetIL.Emit(OpCodes.Ldarg_0);
      numberSetIL.Emit(OpCodes.Ldarg_1);
      numberSetIL.Emit(OpCodes.Stfld, fbNumber);
      numberSetIL.Emit(OpCodes.Ret);

      // Last, map the "get" and "set" accessor methods to the 
      // PropertyBuilder. The property is now complete. 
      pbNumber.SetGetMethod(mbNumberGetAccessor);
      pbNumber.SetSetMethod(mbNumberSetAccessor);

      // Define a method that accepts an integer argument and returns
      // the product of that integer and the private field m_number. This
      // time, the array of parameter types is created on the fly.
      MethodBuilder meth = tb.DefineMethod(
          "MyMethod",
          MethodAttributes.Public,
          typeof(int),
          new Type[] { typeof(int) });

      ILGenerator methIL = meth.GetILGenerator();
      // To retrieve the private instance field, load the instance it
      // belongs to (argument zero). After loading the field, load the 
      // argument one and then multiply. Return from the method with 
      // the return value (the product of the two numbers) on the 
      // execution stack.
      methIL.Emit(OpCodes.Ldarg_0);
      methIL.Emit(OpCodes.Ldfld, fbNumber);
      methIL.Emit(OpCodes.Ldarg_1);
      methIL.Emit(OpCodes.Mul);
      methIL.Emit(OpCodes.Ret);

      // Finish the type.
      Type t = tb.CreateType();

      // The code can be executed immediately. Start by getting reflection
      // objects for the method and the property.
      MethodInfo mi = t.GetMethod("MyMethod");
      PropertyInfo pi = t.GetProperty("Number");

      // Create an instance of MyDynamicType using the default 
      // constructor. 
      object o1 = Activator.CreateInstance(t);

      // Display the value of the property, then change it to 127 and 
      // display it again. Use null to indicate that the property
      // has no index.
      outputBlock.Text += String.Format("o1.Number: {0}\n", pi.GetValue(o1, null));
      pi.SetValue(o1, 127, null);
      outputBlock.Text += String.Format("o1.Number: {0}\n", pi.GetValue(o1, null));

      // Call MyMethod, passing 22, and display the return value, 22
      // times 127. Arguments must be passed as an array, even when
      // there is only one.
      object[] arguments = { 22 };
      outputBlock.Text += String.Format("o1.MyMethod(22): {0}\n",
          mi.Invoke(o1, arguments));

      // Create an instance of MyDynamicType using the constructor
      // that specifies m_Number. The constructor is identified by
      // matching the types in the argument array. In this case, 
      // the argument array is created on the fly. Display the 
      // property value.
      object o2 = Activator.CreateInstance(t,
          new object[] { 5280 });
      outputBlock.Text += String.Format("o2.Number: {0}\n", pi.GetValue(o2, null));
   }
}

/* This code produces the following output:

o1.Number: 42
o1.Number: 127
o1.MyMethod(22): 2794
o2.Number: 5280
 */

Version Information

Silverlight

Supported in: 5, 4, 3

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

Thread Safety

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