DynamicMethod.GetILGenerator 方法

定义

返回可用于发出动态方法的主体的 MSIL 生成器。

重载

GetILGenerator(Int32)

为方法返回一个具有指定 MSIL 流大小的 Microsoft 中间语言 (MSIL) 生成器。

GetILGenerator()

为具有默认 64 字节 Microsoft 中间语言 (MSIL) 流大小的方法返回 MSIL 生成器。

GetILGenerator(Int32)

为方法返回一个具有指定 MSIL 流大小的 Microsoft 中间语言 (MSIL) 生成器。

public:
 System::Reflection::Emit::ILGenerator ^ GetILGenerator(int streamSize);
public System.Reflection.Emit.ILGenerator GetILGenerator (int streamSize);
member this.GetILGenerator : int -> System.Reflection.Emit.ILGenerator
Public Function GetILGenerator (streamSize As Integer) As ILGenerator

参数

streamSize
Int32

MSIL 流的大小(以字节为单位)。

返回

ILGenerator

方法的 ILGenerator 对象,具有指定的 MSIL 流大小。

示例

下面的代码示例演示此方法重载。 此代码示例是为 DynamicMethod 类提供的一个更大示例的一部分。

// Create an array that specifies the parameter types of the
// overload of Console::WriteLine to be used in Hello.
array<Type^>^ writeStringArgs = { String::typeid };
// Get the overload of Console::WriteLine that has one
// String parameter.
MethodInfo^ writeString = Console::typeid->GetMethod("WriteLine", 
    writeStringArgs);

// Get an ILGenerator and emit a body for the dynamic method,
// using a stream size larger than the IL that will be
// emitted.
ILGenerator^ il = hello->GetILGenerator(256);
// Load the first argument, which is a string, onto the stack.
il->Emit(OpCodes::Ldarg_0);
// Call the overload of Console::WriteLine that prints a string.
il->EmitCall(OpCodes::Call, writeString, nullptr);
// The Hello method returns the value of the second argument;
// to do this, load the onto the stack and return.
il->Emit(OpCodes::Ldarg_1);
il->Emit(OpCodes::Ret);
// Create an array that specifies the parameter types of the
// overload of Console.WriteLine to be used in Hello.
Type[] writeStringArgs = {typeof(string)};
// Get the overload of Console.WriteLine that has one
// String parameter.
MethodInfo writeString = typeof(Console).GetMethod("WriteLine",
    writeStringArgs);

// Get an ILGenerator and emit a body for the dynamic method,
// using a stream size larger than the IL that will be
// emitted.
ILGenerator il = hello.GetILGenerator(256);
// Load the first argument, which is a string, onto the stack.
il.Emit(OpCodes.Ldarg_0);
// Call the overload of Console.WriteLine that prints a string.
il.EmitCall(OpCodes.Call, writeString, null);
// The Hello method returns the value of the second argument;
// to do this, load the onto the stack and return.
il.Emit(OpCodes.Ldarg_1);
il.Emit(OpCodes.Ret);
' Create an array that specifies the parameter types of the
' overload of Console.WriteLine to be used in Hello.
Dim writeStringArgs() As Type = {GetType(String)}
' Get the overload of Console.WriteLine that has one
' String parameter.
Dim writeString As MethodInfo = GetType(Console). _
    GetMethod("WriteLine", writeStringArgs) 

' Get an ILGenerator and emit a body for the dynamic method,
' using a stream size larger than the IL that will be
' emitted.
Dim il As ILGenerator = hello.GetILGenerator(256)
' Load the first argument, which is a string, onto the stack.
il.Emit(OpCodes.Ldarg_0)
' Call the overload of Console.WriteLine that prints a string.
il.EmitCall(OpCodes.Call, writeString, Nothing)
' The Hello method returns the value of the second argument;
' to do this, load the onto the stack and return.
il.Emit(OpCodes.Ldarg_1)
il.Emit(OpCodes.Ret)

注解

通过调用 CreateDelegateInvoke 方法完成动态方法后,将忽略任何进一步尝试添加 MSIL。 不会引发异常。

备注

动态方法中的不可验证代码存在限制,即使在某些完全信任方案中也是如此。 请参阅“验证”部分中的 DynamicMethod 注释。

另请参阅

适用于

GetILGenerator()

为具有默认 64 字节 Microsoft 中间语言 (MSIL) 流大小的方法返回 MSIL 生成器。

public:
 System::Reflection::Emit::ILGenerator ^ GetILGenerator();
public System.Reflection.Emit.ILGenerator GetILGenerator ();
member this.GetILGenerator : unit -> System.Reflection.Emit.ILGenerator
Public Function GetILGenerator () As ILGenerator

返回

ILGenerator

该方法的 ILGenerator 对象。

示例

下面的代码示例创建一个采用两个参数的动态方法。 该示例发出一个简单的函数正文,用于将第一个参数打印到控制台,该示例使用第二个参数作为方法的返回值。 该示例通过创建委托、使用不同的参数调用委托,最后使用 Invoke 该方法调用动态方法来完成该方法。

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

public ref class Test
{   
};

// Declare a delegate that will be used to execute the completed
// dynamic method.
delegate int HelloInvoker(String^ msg, int ret);

int main()
{
    // Create an array that specifies the types of the parameters
    // of the dynamic method. This method has a string parameter
    // and an int parameter.
    array<Type^>^ helloArgs = {String::typeid, int::typeid};

    // Create a dynamic method with the name "Hello", a return type
    // of int, and two parameters whose types are specified by the
    // array helloArgs. Create the method in the module that
    // defines the Test class.
    DynamicMethod^ hello = gcnew DynamicMethod("Hello", 
        int::typeid,
        helloArgs,
        Test::typeid->Module);

    // Create an array that specifies the parameter types of the
    // overload of Console.WriteLine to be used in Hello.
    array<Type^>^ writeStringArgs = {String::typeid};
    // Get the overload of Console.WriteLine that has one
    // String parameter.
    MethodInfo^ writeString =
        Console::typeid->GetMethod("WriteLine", writeStringArgs);

    // Get an ILGenerator and emit a body for the dynamic method.
    ILGenerator^ ilgen = hello->GetILGenerator();
    // Load the first argument, which is a string, onto the stack.
    ilgen->Emit(OpCodes::Ldarg_0);
    // Call the overload of Console.WriteLine that prints a string.
    ilgen->EmitCall(OpCodes::Call, writeString, nullptr);
    // The Hello method returns the value of the second argument;
    // to do this, load the onto the stack and return.
    ilgen->Emit(OpCodes::Ldarg_1);
    ilgen->Emit(OpCodes::Ret);

    // Create a delegate that represents the dynamic method. This
    // action completes the method, and any further attempts to
    // change the method will cause an exception.
    HelloInvoker^ helloDelegate =
        (HelloInvoker^) hello->CreateDelegate(HelloInvoker::typeid);

    // Use the delegate to execute the dynamic method. Save and
    // print the return value.
    int returnValue = helloDelegate("\r\nHello, World!", 42);
    Console::WriteLine("helloDelegate(\"Hello, World!\", 42) returned {0}",
        returnValue);

    // Do it again, with different arguments.
    returnValue = helloDelegate("\r\nHi, Mom!", 5280);
    Console::WriteLine("helloDelegate(\"Hi, Mom!\", 5280) returned {0}",
        returnValue);

    // Create an array of arguments to use with the Invoke method.
    array<Object^>^ delegateArgs = {"\r\nHello, World!", 42};
    // Invoke the dynamic method using the arguments. This is much
    // slower than using the delegate, because you must create an
    // array to contain the arguments, and ValueType arguments
    // must be boxed.
    Object^ returnValueObject = hello->Invoke(nullptr, delegateArgs);
    Console::WriteLine("hello.Invoke returned {0}", returnValueObject);
}
using System;
using System.Reflection;
using System.Reflection.Emit;
using Microsoft.VisualBasic;

public class Test
{
    // Declare a delegate that will be used to execute the completed
    // dynamic method.
    private delegate int HelloInvoker(string msg, int ret);

    public static void Main()
    {
        // Create an array that specifies the types of the parameters
        // of the dynamic method. This method has a string parameter
        // and an int parameter.
        Type[] helloArgs = {typeof(string), typeof(int)};

        // Create a dynamic method with the name "Hello", a return type
        // of int, and two parameters whose types are specified by the
        // array helloArgs. Create the method in the module that
        // defines the Test class.
        DynamicMethod hello = new DynamicMethod("Hello",
            typeof(int),
            helloArgs,
            typeof(Test).Module);

        // Create an array that specifies the parameter types of the
        // overload of Console.WriteLine to be used in Hello.
        Type[] writeStringArgs = {typeof(string)};
        // Get the overload of Console.WriteLine that has one
        // String parameter.
        MethodInfo writeString =
            typeof(Console).GetMethod("WriteLine", writeStringArgs);

        // Get an ILGenerator and emit a body for the dynamic method.
        ILGenerator il = hello.GetILGenerator();
        // Load the first argument, which is a string, onto the stack.
        il.Emit(OpCodes.Ldarg_0);
        // Call the overload of Console.WriteLine that prints a string.
        il.EmitCall(OpCodes.Call, writeString, null);
        // The Hello method returns the value of the second argument;
        // to do this, load the onto the stack and return.
        il.Emit(OpCodes.Ldarg_1);
        il.Emit(OpCodes.Ret);

        // Create a delegate that represents the dynamic method. This
        // action completes the method, and any further attempts to
        // change the method will cause an exception.
        HelloInvoker hi =
            (HelloInvoker) hello.CreateDelegate(typeof(HelloInvoker));

        // Use the delegate to execute the dynamic method. Save and
        // print the return value.
        int retval = hi("\r\nHello, World!", 42);
        Console.WriteLine("Executing delegate hi(\"Hello, World!\", 42) returned {0}",
            retval);

        // Do it again, with different arguments.
        retval = hi("\r\nHi, Mom!", 5280);
        Console.WriteLine("Executing delegate hi(\"Hi, Mom!\", 5280) returned {0}",
            retval);

        // Create an array of arguments to use with the Invoke method.
        object[] invokeArgs = {"\r\nHello, World!", 42};
        // Invoke the dynamic method using the arguments. This is much
        // slower than using the delegate, because you must create an
        // array to contain the arguments, and ValueType arguments
        // must be boxed.
        object objRet = hello.Invoke(null, invokeArgs);
        Console.WriteLine("hello.Invoke returned {0}", objRet);
    }
}
Imports System.Reflection
Imports System.Reflection.Emit

Public Class Test
    ' Declare a delegate that will be used to execute the completed
    ' dynamic method. 
    Private Delegate Function HelloInvoker(ByVal msg As String, _
        ByVal ret As Integer) As Integer

    Public Shared Sub Main()
        ' Create an array that specifies the types of the parameters
        ' of the dynamic method. This method has a String parameter
        ' and an Integer parameter.
        Dim helloArgs() As Type = {GetType(String), GetType(Integer)}

        ' Create a dynamic method with the name "Hello", a return type
        ' of Integer, and two parameters whose types are specified by
        ' the array helloArgs. Create the method in the module that
        ' defines the Test class.
        Dim hello As New DynamicMethod("Hello", _
            GetType(Integer), _
            helloArgs, _
            GetType(Test).Module)

        ' Create an array that specifies the parameter types of the
        ' overload of Console.WriteLine to be used in Hello.
        Dim writeStringArgs() As Type = {GetType(String)}
        ' Get the overload of Console.WriteLine that has one
        ' String parameter.
        Dim writeString As MethodInfo = GetType(Console). _
            GetMethod("WriteLine", writeStringArgs) 

        ' Get an ILGenerator and emit a body for the dynamic method.
        Dim il As ILGenerator = hello.GetILGenerator()
        ' Load the first argument, which is a string, onto the stack.
        il.Emit(OpCodes.Ldarg_0)
        ' Call the overload of Console.WriteLine that prints a string.
        il.EmitCall(OpCodes.Call, writeString, Nothing)
        ' The Hello method returns the value of the second argument;
        ' to do this, load the onto the stack and return.
        il.Emit(OpCodes.Ldarg_1)
        il.Emit(OpCodes.Ret)

        ' Create a delegate that represents the dynamic method. This
        ' action completes the method, and any further attempts to
        ' change the method will cause an exception.
    Dim hi As HelloInvoker = _
            hello.CreateDelegate(GetType(HelloInvoker))

        ' Use the delegate to execute the dynamic method. Save and
        ' print the return value.
        Dim retval As Integer = hi(vbCrLf & "Hello, World!", 42)
        Console.WriteLine("Executing delegate hi(""Hello, World!"", 42) returned " _
            & retval)

        ' Do it again, with different arguments.
        retval = hi(vbCrLf & "Hi, Mom!", 5280)
        Console.WriteLine("Executing delegate hi(""Hi, Mom!"", 5280) returned " _
            & retval)

        ' Create an array of arguments to use with the Invoke method.
        Dim invokeArgs() As Object = {vbCrLf & "Hello, World!", 42}
        ' Invoke the dynamic method using the arguments. This is much
        ' slower than using the delegate, because you must create an
        ' array to contain the arguments, and ValueType arguments
        ' must be boxed. Note that this overload of Invoke is 
        ' inherited from MethodBase, and simply calls the more 
        ' complete overload of Invoke.
        Dim objRet As Object = hello.Invoke(Nothing, invokeArgs)
        Console.WriteLine("hello.Invoke returned " & objRet)
    End Sub
End Class

' This code example produces the following output:
'
'Hello, World!
'Executing delegate hi("Hello, World!", 42) returned 42
'
'Hi, Mom!
'Executing delegate hi("Hi, Mom!", 5280) returned 5280
'
'Hello, World!
'hello.Invoke returned 42
'

注解

通过调用 CreateDelegateInvoke 方法完成动态方法后,将忽略任何进一步尝试添加 MSIL。 不会引发异常。

备注

动态方法中的不可验证代码存在限制,即使在某些完全信任方案中也是如此。 请参阅“验证”部分中的 DynamicMethod 注释。

另请参阅

适用于