AssemblyBuilder Classe

Definição

Namespace:

System.Reflection.Emit

Assembly:

System.Reflection.Emit.dll

Source:

AssemblyBuilder.cs

Define e representa um assembly dinâmico.

public ref class AssemblyBuilder abstract : System::Reflection::Assembly

public abstract class AssemblyBuilder : System.Reflection.Assembly

type AssemblyBuilder = class
    inherit Assembly

Public MustInherit Class AssemblyBuilder
Inherits Assembly

Herança

Object

Assembly

AssemblyBuilder

Exemplos

O exemplo de código a seguir mostra como definir e usar um assembly dinâmico. O assembly de exemplo contém um tipo, MyDynamicType, que tem um campo privado, uma propriedade que obtém e define o campo privado, construtores que inicializam o campo privado e um método que multiplica um número fornecido pelo usuário pelo valor de campo privado e retorna o resultado.

using namespace System;
using namespace System::Reflection;
using namespace System::Reflection::Emit;

void main()
{
    // This code creates an assembly that contains one type,
    // named "MyDynamicType", that 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 Visual C++ the type might look like this:
    /*
      public ref class MyDynamicType
      {
      private:
          int m_number;

      public:
          MyDynamicType() : m_number(42) {};
          MyDynamicType(int initNumber) : m_number(initNumber) {};
      
          property int Number
          {
              int get() { return m_number; }
              void set(int value) { m_number = value; }
          }

          int MyMethod(int multiplier)
          {
              return m_number * multiplier;
          }
      };
    */
      
    AssemblyName^ aName = gcnew AssemblyName("DynamicAssemblyExample");
    AssemblyBuilder^ ab = 
        AssemblyBuilder::DefineDynamicAssembly(
            aName, 
            AssemblyBuilderAccess::Run);

    // The module name is usually the same as the assembly name
    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", 
        int::typeid, 
        FieldAttributes::Private);

    // Define a constructor that takes an integer argument and 
    // stores it in the private field. 
    array<Type^>^ parameterTypes = { int::typeid };
    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, 
        Object::typeid->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 nullptr.
    ConstructorBuilder^ ctor0 = tb->DefineConstructor(
        MethodAttributes::Public, 
        CallingConventions::Standard, 
        Type::EmptyTypes);

    ILGenerator^ ctor0IL = ctor0->GetILGenerator();
    ctor0IL->Emit(OpCodes::Ldarg_0);
    ctor0IL->Emit(OpCodes::Call, 
        Object::typeid->GetConstructor(Type::EmptyTypes));
    // 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.
    ctor0IL->Emit(OpCodes::Ldarg_0);
    ctor0IL->Emit(OpCodes::Ldc_I4_S, 42);
    ctor0IL->Emit(OpCodes::Stfld, fbNumber);
    ctor0IL->Emit(OpCodes::Ret);

    // Define a property named Number that gets and sets the private 
    // field.
    //
    // The last argument of DefineProperty is nullptr, because the
    // property has no parameters. (If you don't specify nullptr, 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, 
        int::typeid, 
        nullptr);
      
    // 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 nullptr could be 
    // used instead of Types::EmptyTypes)
    MethodBuilder^ mbNumberGetAccessor = tb->DefineMethod(
        "get_Number", 
        getSetAttr, 
        int::typeid, 
        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, 
        nullptr, 
        gcnew array<Type^> { int::typeid });
      
    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, 
        int::typeid, 
        gcnew array<Type^> { int::typeid });

    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();

    // Because AssemblyBuilderAccess includes Run, 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 nullptr to indicate that the property
    // has no index.
    Console::WriteLine("o1->Number: {0}", pi->GetValue(o1, nullptr));
    pi->SetValue(o1, 127, nullptr);
    Console::WriteLine("o1->Number: {0}", pi->GetValue(o1, nullptr));

    // 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.
    array<Object^>^ arguments = { 22 };
    Console::WriteLine("o1->MyMethod(22): {0}", 
        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, 
        gcnew array<Object^> { 5280 });
    Console::WriteLine("o2->Number: {0}", pi->GetValue(o2, nullptr));
};

/* 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 DemoAssemblyBuilder
{
    public static void Main()
    {
        // This code creates an assembly that contains one type,
        // named "MyDynamicType", that 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;
            }
        }
        */

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

        // The module name is usually the same as the assembly name.
        ModuleBuilder mb = ab.DefineDynamicModule(aName.Name ?? "DynamicAssemblyExample");

        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);
        ConstructorInfo? ci = typeof(object).GetConstructor(Type.EmptyTypes);
        ctor1IL.Emit(OpCodes.Call, ci!);
        // 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();

        // Because AssemblyBuilderAccess includes Run, 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 = null;
        if (t is not null)
            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.
        Console.WriteLine("o1.Number: {0}", pi?.GetValue(o1, null));
        pi?.SetValue(o1, 127, null);
        Console.WriteLine("o1.Number: {0}", 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 };
        Console.WriteLine("o1.MyMethod(22): {0}",
            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 = null;
        if (t is not null)
            Activator.CreateInstance(t, new object[] { 5280 });
        Console.WriteLine("o2.Number: {0}", pi?.GetValue(o2, null));
    }
}

/* This code produces the following output:

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

open System
open System.Threading
open System.Reflection
open System.Reflection.Emit

// This code creates an assembly that contains one type,
// named "MyDynamicType", that 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;
    }
}
*)

let assemblyName = new AssemblyName("DynamicAssemblyExample")
let assemblyBuilder =
    AssemblyBuilder.DefineDynamicAssembly(
        assemblyName,
        AssemblyBuilderAccess.Run)

// The module name is usually the same as the assembly name.
let moduleBuilder =
    assemblyBuilder.DefineDynamicModule(assemblyName.Name)

let typeBuilder =
    moduleBuilder.DefineType(
        "MyDynamicType",
        TypeAttributes.Public)

// Add a private field of type int (Int32)
let fieldBuilderNumber =
    typeBuilder.DefineField(
        "m_number",
        typeof<int>,
        FieldAttributes.Private)

// Define a constructor1 that takes an integer argument and
// stores it in the private field.
let parameterTypes = [| typeof<int> |]
let ctor1 =
    typeBuilder.DefineConstructor(
        MethodAttributes.Public,
        CallingConventions.Standard,
        parameterTypes)

let 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<obj>.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, fieldBuilderNumber)
ctor1IL.Emit(OpCodes.Ret)

// Define a default constructor1 that supplies a default value
// for the private field. For parameter types, pass the empty
// array of types or pass null.
let ctor0 =
    typeBuilder.DefineConstructor(
        MethodAttributes.Public,
        CallingConventions.Standard,
        Type.EmptyTypes)

let 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)
let propertyBuilderNumber =
    typeBuilder.DefineProperty(
        "Number",
        PropertyAttributes.HasDefault,
        typeof<int>,
        null)

// The property "set" and property "get" methods require a special
// set of attributes.
let 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)
let methodBuilderNumberGetAccessor =
    typeBuilder.DefineMethod(
        "get_number",
        getSetAttr,
        typeof<int>,
        Type.EmptyTypes)

let numberGetIL =
    methodBuilderNumberGetAccessor.GetILGenerator()

// For an instance property, argument zero ir 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, fieldBuilderNumber)
numberGetIL.Emit(OpCodes.Ret)

// Define the "set" accessor method for Number, which has no return
// type and takes one argument of type int (Int32).
let methodBuilderNumberSetAccessor =
    typeBuilder.DefineMethod(
        "set_number",
        getSetAttr,
        null,
        [| typeof<int> |])

let numberSetIL =
    methodBuilderNumberSetAccessor.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, fieldBuilderNumber)
numberSetIL.Emit(OpCodes.Ret)

// Last, map the "get" and "set" accessor methods to the
// PropertyBuilder. The property is now complete.
propertyBuilderNumber.SetGetMethod(methodBuilderNumberGetAccessor)
propertyBuilderNumber.SetSetMethod(methodBuilderNumberSetAccessor)

// 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.
let methodBuilder =
    typeBuilder.DefineMethod(
        "MyMethod",
        MethodAttributes.Public,
        typeof<int>,
        [| typeof<int> |])

let methodIL = methodBuilder.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.
methodIL.Emit(OpCodes.Ldarg_0)
methodIL.Emit(OpCodes.Ldfld, fieldBuilderNumber)
methodIL.Emit(OpCodes.Ldarg_1)
methodIL.Emit(OpCodes.Mul)
methodIL.Emit(OpCodes.Ret)

// Finish the type
let typ = typeBuilder.CreateType()

// Because AssemblyBuilderAccess includes Run, the code can be
// executed immediately. Start by getting reflection objects for
// the method and the property.
let methodInfo = typ.GetMethod("MyMethod")
let propertyInfo = typ.GetProperty("Number")

// Create an instance of MyDynamicType using the default
// constructor.
let obj1 = Activator.CreateInstance(typ)

// 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.
printfn "obj1.Number: %A" (propertyInfo.GetValue(obj1, null))
propertyInfo.SetValue(obj1, 127, null)
printfn "obj1.Number: %A" (propertyInfo.GetValue(obj1, null))

// Call MyMethod, pasing 22, and display the return value, 22
// times 127. Arguments must be passed as an array, even when
// there is only one.
let arguments: obj array = [| 22 |]
printfn "obj1.MyMethod(22): %A" (methodInfo.Invoke(obj1, 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.
let constructorArguments: obj array = [| 5280 |]
let obj2 = Activator.CreateInstance(typ, constructorArguments)
printfn "obj2.Number: %A" (propertyInfo.GetValue(obj2, null))

(* This code produces the following output:

obj1.Number: 42
obj1.Number: 127
obj1.MyMethod(22): 2794
obj1.Number: 5280
*)

Imports System.Reflection
Imports System.Reflection.Emit

Class DemoAssemblyBuilder

    Public Shared Sub Main()

        ' This code creates an assembly that contains one type,
        ' named "MyDynamicType", that 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
        'End Class
      
        Dim aName As New AssemblyName("DynamicAssemblyExample")
        Dim ab As AssemblyBuilder = _
            AssemblyBuilder.DefineDynamicAssembly( _
                aName, _
                AssemblyBuilderAccess.Run)

        ' The module name is usually the same as the assembly name.
        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()

        ' Because AssemblyBuilderAccess includes Run, 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.
        Console.WriteLine("o1.Number: {0}", pi.GetValue(o1, Nothing))
        pi.SetValue(o1, 127, Nothing)
        Console.WriteLine("o1.Number: {0}", 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 }
        Console.WriteLine("o1.MyMethod(22): {0}", _
            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 })
        Console.WriteLine("o2.Number: {0}", 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

Comentários

Para obter mais informações sobre essa API, consulte Comentários de API complementares para AssemblyBuilder.

Construtores

AssemblyBuilder()

Inicializa uma nova instância da classe AssemblyBuilder.

Propriedades

CodeBase	Obsoleto. Obtém o local do assembly como especificado originalmente (como em um objeto AssemblyName).
CustomAttributes	Obtém uma coleção que contém os atributos personalizados deste assembly. (Herdado de Assembly)
DefinedTypes	Obtém uma coleção dos tipos definidos nesse assembly. (Herdado de Assembly)
EntryPoint	Retorna o ponto de entrada desse assembly.
EscapedCodeBase	Obsoleto. Obtém o URI, incluindo caracteres de escape, que representa a base de código. (Herdado de Assembly)
Evidence	Obtém a evidência para esse assembly. (Herdado de Assembly)
ExportedTypes	Obtém uma coleção dos tipos públicos definidos nesse assembly visíveis fora do assembly. (Herdado de Assembly)
FullName	Obtém o nome de exibição do assembly dinâmico atual.
GlobalAssemblyCache	Obsoleto. Obtém um valor que indica se o assembly foi carregado do cache de assembly global (somente .NET Framework). (Herdado de Assembly)
HostContext	Obtém o contexto do host em que o assembly dinâmico está sendo criado.
ImageRuntimeVersion	Obtém uma cadeia de caracteres que representa a versão do CLR (Common Language Runtime) salva no arquivo que contém o manifesto. (Herdado de Assembly)
IsCollectible	Obtém um valor que indica se esse assembly dinâmico é mantido em um colecionável AssemblyLoadContext.
IsDynamic	Obtém um valor que indica que o assembly atual é um assembly dinâmico.
IsFullyTrusted	Obtém um valor que indica se o assembly atual é carregado com confiança total. (Herdado de Assembly)
Location	Obtém o local, no formato de base de código, do arquivo carregado que contém o manifesto, caso não tenha sido feita cópia de sombra dele.
ManifestModule	Obtém o módulo no AssemblyBuilder atual que contém o manifesto do assembly.
Modules	Obtém uma coleção que contém os módulos neste assembly. (Herdado de Assembly)
PermissionSet	Obtém o conjunto de concessões do assembly atual. (Herdado de Assembly)
ReflectionOnly	Obtém um valor que indica se o assembly dinâmico está no contexto de somente reflexão.
SecurityRuleSet	Obtém um valor que indica qual conjunto de regras de segurança o CLR (Common Language Runtime) impõe a este assembly. (Herdado de Assembly)

Métodos

CreateInstance(String)	Localiza o tipo especificado desse assembly e cria uma instância dele usando o ativador de sistema, usando a pesquisa que diferencia maiúsculas de minúsculas. (Herdado de Assembly)
CreateInstance(String, Boolean)	Localiza o tipo especificado desse assembly e cria uma instância dele usando o ativador de sistema, com pesquisa que diferencia maiúsculas de minúsculas opcional. (Herdado de Assembly)
CreateInstance(String, Boolean, BindingFlags, Binder, Object[], CultureInfo, Object[])	Localiza o tipo especificado desse assembly e cria uma instância dele usando o ativador do sistema, com a pesquisa opcional que diferencia maiúsculas de minúsculas e com a cultura especificada, os argumentos e os atributos de associação e ativação. (Herdado de Assembly)
DefineDynamicAssembly(AssemblyName, AssemblyBuilderAccess)	Define um assembly dinâmico que tem o nome e os direitos de acesso especificados.
DefineDynamicAssembly(AssemblyName, AssemblyBuilderAccess, IEnumerable<CustomAttributeBuilder>)	Define um novo assembly que tem o nome, os direitos de acesso e os atributos especificados.
DefineDynamicModule(String)	Define um módulo dinâmico transitório nomeado nesse assembly.
DefineDynamicModuleCore(String)	Quando substituído em uma classe derivada, define um módulo dinâmico neste assembly.
Equals(Object)	Retorna um valor que indica se esta instância é igual ao objeto especificado.
GetCustomAttributes(Boolean)	Retorna todos os atributos personalizados que foram aplicados ao AssemblyBuilder atual.
GetCustomAttributes(Type, Boolean)	Retorna todos os atributos personalizados que foram aplicados ao AssemblyBuilder atual e que derivam de um tipo de atributo especificado.
GetCustomAttributesData()	Retorna objetos CustomAttributeData que contêm informações sobre os atributos que foram aplicados ao AssemblyBuilder atual.
GetDynamicModule(String)	Retorna o módulo dinâmico com o nome especificado.
GetDynamicModuleCore(String)	Quando substituído em uma classe derivada, retorna o módulo dinâmico com o nome especificado.
GetExportedTypes()	Obtém os tipos exportados definidos neste assembly.
GetFile(String)	Obtém um FileStream para o arquivo especificado na tabela de arquivo do manifesto desse assembly.
GetFiles()	Obtém os arquivos na tabela de arquivo de um manifesto do assembly. (Herdado de Assembly)
GetFiles(Boolean)	Obtém os arquivos na tabela de arquivos de um manifesto do assembly, especificando se deseja-se incluir os módulos de recursos.
GetForwardedTypes()	Define e representa um assembly dinâmico. (Herdado de Assembly)
GetHashCode()	Retorna o código hash para a instância.
GetLoadedModules()	Obtém todos os módulos carregados que fazem parte desse assembly. (Herdado de Assembly)
GetLoadedModules(Boolean)	Retorna todos os módulos carregados que fazem parte desse assembly e, opcionalmente, inclui módulos de recursos.
GetManifestResourceInfo(String)	Retorna informações sobre como o recurso em questão foi persistido.
GetManifestResourceNames()	Carrega o recurso de manifesto especificado desse assembly.
GetManifestResourceStream(String)	Carrega o recurso de manifesto especificado desse assembly.
GetManifestResourceStream(Type, String)	Carrega o recurso de manifesto especificado, o escopo pelo namespace do tipo especificado, desse assembly.
GetModule(String)	Obtém o módulo especificado nesse assembly.
GetModules()	Obtém todos os módulos que fazem parte desse assembly. (Herdado de Assembly)
GetModules(Boolean)	Obtém todos os módulos que fazem parte desse assembly e, opcionalmente, inclui módulos de recursos.
GetName()	Obtém um AssemblyName para esse assembly. (Herdado de Assembly)
GetName(Boolean)	Obtém o AssemblyName, que foi especificado quando o assembly dinâmico atual foi criado e define a base de código como especificado.
GetObjectData(SerializationInfo, StreamingContext)	Obsoleto. Obtém informações de serialização com todos os dados necessários para recriar uma instância desse assembly. (Herdado de Assembly)
GetReferencedAssemblies()	Obtém uma lista incompleta de objetos AssemblyName para os assemblies que são referenciados por este AssemblyBuilder.
GetSatelliteAssembly(CultureInfo)	Obtém o assembly satélite para a cultura especificada.
GetSatelliteAssembly(CultureInfo, Version)	Obtém a versão especificada do assembly satélite para a cultura especificada.
GetType()	Define e representa um assembly dinâmico. (Herdado de Assembly)
GetType(String)	Obtém o objeto Type com o nome especificado na instância do assembly. (Herdado de Assembly)
GetType(String, Boolean)	Obtém o objeto Type com o nome especificado na instância do assembly e, opcionalmente, lança uma exceção se o tipo não for encontrado. (Herdado de Assembly)
GetType(String, Boolean, Boolean)	Obtém o tipo especificado dos tipos que foram definidos e criados no AssemblyBuilder atual.
GetTypes()	Obtém todos os tipos definidos neste assembly. (Herdado de Assembly)
IsDefined(Type, Boolean)	Retorna um valor que indica se uma ou mais instâncias do tipo de atributo especificado será aplicada a esse membro.
LoadModule(String, Byte[])	Carrega o módulo, interno a esse assembly, com uma imagem baseada no formato COFF que contém um módulo emitido ou um arquivo de recurso. (Herdado de Assembly)
LoadModule(String, Byte[], Byte[])	Carrega o módulo, interno a esse assembly, com uma imagem baseada no formato COFF que contém um módulo emitido ou um arquivo de recurso. Os bytes brutos que representam os símbolos para o módulo também são carregados. (Herdado de Assembly)
MemberwiseClone()	Cria uma cópia superficial do Object atual. (Herdado de Object)
SetCustomAttribute(ConstructorInfo, Byte[])	Defina um atributo personalizado neste assembly usando um blob de atributos personalizados especificado.
SetCustomAttribute(CustomAttributeBuilder)	Defina um atributo personalizado neste assembly usando um construtor de atributos personalizados.
SetCustomAttributeCore(ConstructorInfo, ReadOnlySpan<Byte>)	Quando substituído em uma classe derivada, define um atributo personalizado neste assembly.
ToString()	Retorna o nome completo do assembly, também conhecido como o nome de exibição. (Herdado de Assembly)

Eventos

ModuleResolve

Ocorre quando o carregador de classe do Common Language Runtime não é capaz de resolver uma referência a um módulo interno de um assembly por meios normais. (Herdado de Assembly)

Métodos de Extensão

GetExportedTypes(Assembly)	Define e representa um assembly dinâmico.
GetModules(Assembly)	Define e representa um assembly dinâmico.
GetTypes(Assembly)	Define e representa um assembly dinâmico.
GetCustomAttribute(Assembly, Type)	Recupera um atributo personalizado de um tipo especificado aplicado a um assembly especificado.
GetCustomAttribute<T>(Assembly)	Recupera um atributo personalizado de um tipo especificado aplicado a um assembly especificado.
GetCustomAttributes(Assembly)	Recupera uma coleção de atributos personalizados que são aplicados a um assembly especificado.
GetCustomAttributes(Assembly, Type)	Recupera uma coleção de atributos personalizados de um tipo especificado que são aplicados a um assembly especificado.
GetCustomAttributes<T>(Assembly)	Recupera uma coleção de atributos personalizados de um tipo especificado que são aplicados a um assembly especificado.
IsDefined(Assembly, Type)	Indica se os atributos personalizados de um tipo especificados são aplicados a um assembly especificado.
TryGetRawMetadata(Assembly, Byte*, Int32)	Recupera a seção de metadados do assembly, para uso com MetadataReader.

Confira também

• DefineDynamicAssembly
• Emitindo métodos e assemblies dinâmicos