AssemblyBuilder 类

定义

命名空间:

System.Reflection.Emit

程序集:

System.Reflection.Emit.dll

Source:

AssemblyBuilder.cs

定义并表示动态程序集。

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

继承

Object

Assembly

AssemblyBuilder

派生

System.Reflection.Emit.PersistedAssemblyBuilder

示例

下面的代码示例演示如何定义和使用动态程序集。 示例程序集包含一个类型，MyDynamicType，该类型具有专用字段、获取和设置专用字段的属性、初始化专用字段的构造函数，以及将用户提供的数字乘以专用字段值并返回结果的方法。

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)
            o2 = 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

注解

有关此 API 的详细信息，请参阅 assemblyBuilder的 补充 API 备注。

构造函数

AssemblyBuilder()

初始化 AssemblyBuilder 类的新实例。

属性

CodeBase	已过时. 获取程序集的位置，如最初指定的（如在 AssemblyName 对象中）。
CustomAttributes	获取包含此程序集的自定义属性的集合。 (继承自 Assembly)
DefinedTypes	获取此程序集中定义的类型的集合。 (继承自 Assembly)
EntryPoint	返回此程序集的入口点。
EscapedCodeBase	已过时. 获取表示代码库的 URI（包括转义字符）。 (继承自 Assembly)
Evidence	获取此程序集的证据。 (继承自 Assembly)
ExportedTypes	获取此程序集中定义的公共类型的集合，这些类型在程序集外部可见。 (继承自 Assembly)
FullName	获取当前动态程序集的显示名称。
GlobalAssemblyCache	已过时. 获取一个值，该值指示程序集是否已从全局程序集缓存（.NET Framework）加载。 (继承自 Assembly)
HostContext	获取正在在其中创建动态程序集的主机上下文。
ImageRuntimeVersion	获取一个字符串，该字符串表示包含在包含清单的文件中保存的公共语言运行时 （CLR） 的版本。 (继承自 Assembly)
IsCollectible	获取一个值，该值指示此动态程序集是否保存在可收集 AssemblyLoadContext中。
IsDynamic	获取一个值，该值指示当前程序集是动态程序集。
IsFullyTrusted	获取一个值，该值指示当前程序集是否使用完全信任加载。 (继承自 Assembly)
Location	获取加载的文件的位置（以代码库格式获取，如果该文件不是卷影复制的）。
ManifestModule	获取包含程序集清单的当前 AssemblyBuilder 中的模块。
Modules	获取包含此程序集中的模块的集合。 (继承自 Assembly)
PermissionSet	获取当前程序集的授权集。 (继承自 Assembly)
ReflectionOnly	获取一个值，该值指示动态程序集是否位于仅反射上下文中。
SecurityRuleSet	获取一个值，该值指示公共语言运行时（CLR）为此程序集强制执行的安全规则集。 (继承自 Assembly)

方法

CreateInstance(String)	找到此程序集中的指定类型，并使用系统激活器（使用区分大小写的搜索）创建它的实例。 (继承自 Assembly)
CreateInstance(String, Boolean)	查找此程序集中的指定类型，并使用系统激活器创建它的实例，以及可选的区分大小写的搜索。 (继承自 Assembly)
CreateInstance(String, Boolean, BindingFlags, Binder, Object[], CultureInfo, Object[])	从此程序集中找到指定的类型，并使用系统激活器创建它的实例，并具有可选的区分大小写的搜索，并具有指定的区域性、参数以及绑定和激活属性。 (继承自 Assembly)
DefineDynamicAssembly(AssemblyName, AssemblyBuilderAccess)	定义具有指定名称和访问权限的动态程序集。
DefineDynamicAssembly(AssemblyName, AssemblyBuilderAccess, IEnumerable<CustomAttributeBuilder>)	定义具有指定名称、访问权限和属性的新程序集。
DefineDynamicModule(String)	在此程序集中定义一个命名的暂时性动态模块。
DefineDynamicModuleCore(String)	在派生类中重写时，在此程序集中定义动态模块。
Equals(Object)	返回一个值，该值指示此实例是否等于指定的对象。
GetCustomAttributes(Boolean)	返回已应用于当前 AssemblyBuilder的所有自定义属性。
GetCustomAttributes(Type, Boolean)	返回已应用于当前 AssemblyBuilder的所有自定义属性，以及派生自指定属性类型的所有自定义属性。
GetCustomAttributesData()	返回 CustomAttributeData 对象，这些对象包含已应用于当前 AssemblyBuilder的属性的相关信息。
GetDynamicModule(String)	返回具有指定名称的动态模块。
GetDynamicModuleCore(String)	在派生类中重写时，返回具有指定名称的动态模块。
GetExportedTypes()	获取此程序集中定义的导出类型。
GetFile(String)	获取此程序集清单的文件表中指定文件的 FileStream。
GetFiles()	获取程序集清单的文件表中的文件。 (继承自 Assembly)
GetFiles(Boolean)	获取程序集清单的文件表中的文件，指定是否包含资源模块。
GetForwardedTypes()	定义并表示动态程序集。 (继承自 Assembly)
GetHashCode()	返回此实例的哈希代码。
GetLoadedModules()	获取属于此程序集的所有已加载模块。 (继承自 Assembly)
GetLoadedModules(Boolean)	返回属于此程序集的所有已加载模块，并选择性地包括资源模块。
GetManifestResourceInfo(String)	返回有关如何持久保存给定资源的信息。
GetManifestResourceNames()	从此程序集加载指定的清单资源。
GetManifestResourceStream(String)	从此程序集加载指定的清单资源。
GetManifestResourceStream(Type, String)	从此程序集加载由指定类型的命名空间限定的指定清单资源。
GetModule(String)	获取此程序集中的指定模块。
GetModules()	获取属于此程序集的所有模块。 (继承自 Assembly)
GetModules(Boolean)	获取属于此程序集的所有模块，并选择性地包括资源模块。
GetName()	获取此程序集的 AssemblyName。 (继承自 Assembly)
GetName(Boolean)	获取在创建当前动态程序集时指定的 AssemblyName，并按指定设置代码库。
GetObjectData(SerializationInfo, StreamingContext)	已过时. 获取序列化信息，其中包含重新初始化此程序集所需的所有数据。 (继承自 Assembly)
GetReferencedAssemblies()	获取此 AssemblyBuilder引用的程序集的 AssemblyName 对象的不完整列表。
GetSatelliteAssembly(CultureInfo)	获取指定区域性的附属程序集。
GetSatelliteAssembly(CultureInfo, Version)	获取指定区域性的附属程序集的指定版本。
GetType()	定义并表示动态程序集。 (继承自 Assembly)
GetType(String)	获取程序集实例中具有指定名称的 Type 对象。 (继承自 Assembly)
GetType(String, Boolean)	获取程序集实例中具有指定名称的 Type 对象，并选择性地在找不到类型时引发异常。 (继承自 Assembly)
GetType(String, Boolean, Boolean)	从当前 AssemblyBuilder中定义的和创建的类型中获取指定类型。
GetTypes()	获取此程序集中定义的所有类型。 (继承自 Assembly)
IsDefined(Type, Boolean)	返回一个值，该值指示指定属性类型的一个或多个实例是否应用于此成员。
LoadModule(String, Byte[])	将模块加载到此程序集的内部，其中包含一个基于公共对象文件格式（COFF）的图像，其中包含发出的模块或资源文件。 (继承自 Assembly)
LoadModule(String, Byte[], Byte[])	将模块加载到此程序集的内部，其中包含一个基于公共对象文件格式（COFF）的图像，其中包含发出的模块或资源文件。 还将加载表示模块符号的原始字节。 (继承自 Assembly)
MemberwiseClone()	创建当前 Object的浅表副本。 (继承自 Object)
SetCustomAttribute(ConstructorInfo, Byte[])	使用指定的自定义属性 blob 在此程序集上设置自定义属性。
SetCustomAttribute(CustomAttributeBuilder)	使用自定义属性生成器在此程序集上设置自定义属性。
SetCustomAttributeCore(ConstructorInfo, ReadOnlySpan<Byte>)	在派生类中重写时，在此程序集上设置自定义属性。
ToString()	返回程序集的完整名称，也称为显示名称。 (继承自 Assembly)

事件

ModuleResolve

当公共语言运行时类加载程序无法通过正常方式解析对程序集内部模块的引用时发生。 (继承自 Assembly)

扩展方法

GetExportedTypes(Assembly)	定义并表示动态程序集。
GetModules(Assembly)	定义并表示动态程序集。
GetTypes(Assembly)	定义并表示动态程序集。
GetCustomAttribute(Assembly, Type)	检索应用于指定程序集的指定类型的自定义属性。
GetCustomAttribute<T>(Assembly)	检索应用于指定程序集的指定类型的自定义属性。
GetCustomAttributes(Assembly)	检索应用于指定程序集的自定义属性的集合。
GetCustomAttributes(Assembly, Type)	检索应用于指定程序集的指定类型的自定义属性集合。
GetCustomAttributes<T>(Assembly)	检索应用于指定程序集的指定类型的自定义属性集合。
IsDefined(Assembly, Type)	指示指定类型的自定义属性是否应用于指定的程序集。
TryGetRawMetadata(Assembly, Byte*, Int32)	检索程序集的元数据部分，以用于 MetadataReader。

另请参阅

• DefineDynamicAssembly
• 发出动态方法和程序集