次の方法で共有


MethodRental.SwapMethodBody(Type, Int32, IntPtr, Int32, Int32) メソッド

定義

メソッドの本体を交換します。

public:
 static void SwapMethodBody(Type ^ cls, int methodtoken, IntPtr rgIL, int methodSize, int flags);
public static void SwapMethodBody (Type cls, int methodtoken, IntPtr rgIL, int methodSize, int flags);
static member SwapMethodBody : Type * int * nativeint * int * int -> unit
Public Shared Sub SwapMethodBody (cls As Type, methodtoken As Integer, rgIL As IntPtr, methodSize As Integer, flags As Integer)

パラメーター

cls
Type

メソッドを格納しているクラス。

methodtoken
Int32

メソッドのトークン。

rgIL
IntPtr

nativeint

メソッドを指すポインター。 これにはメソッド ヘッダーが含まれます。

methodSize
Int32

新しいメソッド本体のサイズ (バイト単位)。

flags
Int32

交換を制御するフラグ。 定数の定義を参照してください。

例外

clsnullです。

cls が不完全です。

methodSize が 0 未満、または 4128767 (16 進数 3effff) を超えます。

次の例は、メソッド本体を新しい本文に入れ替える方法を示しています。 また、既存のメソッドのメソッド トークンを取得する方法と、 に渡される Microsoft Intermediate Language (MSIL) コードを表すバイトの BLOB を構築する SwapMethodBody方法についても説明します。

using namespace System;
using namespace System::Reflection;
using namespace System::Reflection::Emit;
using namespace System::Runtime::InteropServices;

// First make a method that returns 0.
// Then swap the method body with a body that returns 1.
int main()
{
   // Construct a dynamic assembly
   Guid g = Guid::NewGuid();
   AssemblyName^ asmname = gcnew AssemblyName;
   asmname->Name = String::Concat( "tempfile", g );
   AssemblyBuilder^ asmbuild = System::Threading::Thread::GetDomain()->DefineDynamicAssembly( asmname, AssemblyBuilderAccess::Run );

   // Add a dynamic module that contains one type that has one method that
   // has no arguments.
   ModuleBuilder^ modbuild = asmbuild->DefineDynamicModule( "test" );
   TypeBuilder^ tb = modbuild->DefineType( "name of the Type" );
   array<Type^>^temp2;
   MethodBuilder^ somemethod = tb->DefineMethod( "My method Name", static_cast<MethodAttributes>(MethodAttributes::Public | MethodAttributes::Static), int::typeid, temp2 );

   // Define the body of the method to return 0.
   ILGenerator^ ilg = somemethod->GetILGenerator();
   ilg->Emit( OpCodes::Ldc_I4_0 );
   ilg->Emit( OpCodes::Ret );

   // Complete the type and verify that it returns 0.
   Type^ tbBaked = tb->CreateType();
   array<Object^>^temp0;
   int res1 = safe_cast<Int32>(tbBaked->GetMethod( "My method Name" )->Invoke( nullptr, temp0 ));
   if ( res1 != 0 )
   {
      Console::WriteLine( "Err_001a, should have returned 0" );
   }
   else
   {
      Console::WriteLine( "Original method returned 0" );
   }

   // Define a new method body that will return a 1 instead.

   // code size
   // ldc_i4_1
   // ret
   array<Byte>^methodBytes = {0x03,0x30,0x0A,0x00,0x02,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x17,0x2a};

   // Get the token for the method whose body you are replacing.
   MethodToken somemethodToken = somemethod->GetToken();

   // Get the pointer to the method body.
   GCHandle hmem = GCHandle::Alloc( (Object^)methodBytes, GCHandleType::Pinned );
   IntPtr addr = hmem.AddrOfPinnedObject();
   int cbSize = methodBytes->Length;

   // Swap the old method body with the new body.
   MethodRental::SwapMethodBody( tbBaked, somemethodToken.Token, addr, cbSize, MethodRental::JitImmediate );

   // Verify that the modified method returns 1.
   array<Object^>^temp1;
   int res2 = safe_cast<Int32>(tbBaked->GetMethod( "My method Name" )->Invoke( nullptr, temp1 ));
   if ( res2 != 1 )
   {
      Console::WriteLine( "Err_001b, should have returned 1" );
   }
   else
   {
      Console::WriteLine( "Swapped method body returned 1" );
   }
}
using System;
using System.Reflection;
using System.Reflection.Emit;
using System.Runtime.InteropServices;

class SwapMethodBodySample
{
    // First make a method that returns 0.
    // Then swap the method body with a body that returns 1.
    public static void Main(string [] args)
    {
    // Construct a dynamic assembly
    Guid g = Guid.NewGuid();
    AssemblyName asmname = new AssemblyName();
    asmname.Name = "tempfile" + g;
    AssemblyBuilder asmbuild = System.Threading.Thread.GetDomain().
        DefineDynamicAssembly(asmname, AssemblyBuilderAccess.Run);

    // Add a dynamic module that contains one type that has one method that
    // has no arguments.
    ModuleBuilder modbuild = asmbuild.DefineDynamicModule( "test");
        TypeBuilder tb = modbuild.DefineType( "name of the Type" );
        MethodBuilder somemethod = tb.DefineMethod
            ("My method Name",
             MethodAttributes.Public | MethodAttributes.Static,
             typeof(int),
             new Type[]{} );
    // Define the body of the method to return 0.
        ILGenerator ilg = somemethod.GetILGenerator();
    ilg.Emit(OpCodes.Ldc_I4_0);
    ilg.Emit(OpCodes.Ret);

    // Complete the type and verify that it returns 0.
    Type tbBaked = tb.CreateType();
    int res1 = (int)tbBaked.GetMethod("My method Name").Invoke( null, new Object[]{} );
    if ( res1 != 0 ) {
        Console.WriteLine( "Err_001a, should have returned 0" );
    } else {
        Console.WriteLine("Original method returned 0");
    }

    // Define a new method body that will return a 1 instead.
    Byte[] methodBytes = {
        0x03,
        0x30,
        0x0A,
        0x00,
        0x02,                // code size
        0x00,
        0x00,
        0x00,
        0x00,
        0x00,
        0x00,
        0x00,
        0x17,                // ldc_i4_1
        0x2a                // ret
    };

    // Get the token for the method whose body you are replacing.
    MethodToken somemethodToken = somemethod.GetToken();

    // Get the pointer to the method body.
        GCHandle hmem = GCHandle.Alloc((Object) methodBytes, GCHandleType.Pinned);
        IntPtr addr = hmem.AddrOfPinnedObject();
    int cbSize = methodBytes.Length;

    // Swap the old method body with the new body.
    MethodRental.SwapMethodBody(
                    tbBaked,
                    somemethodToken.Token,
                    addr,
                    cbSize,
                    MethodRental.JitImmediate);

    // Verify that the modified method returns 1.
    int res2 = (int)tbBaked.GetMethod("My method Name").Invoke( null, new Object[]{} );
    if ( res2 != 1 ) {
        Console.WriteLine( "Err_001b, should have returned 1" );
    } else {
        Console.WriteLine("Swapped method body returned 1");
    }
    }
}
Imports System.Reflection
Imports System.Reflection.Emit
Imports System.Runtime.InteropServices

Class SwapMethodBodySample
    
    ' First make a method that returns 0.
    ' Then swap the method body with a body that returns 1.
    Public Shared Sub Main()
        ' Construct a dynamic assembly
        Dim g As Guid = Guid.NewGuid()
        Dim asmname As New AssemblyName()
        asmname.Name = "tempfile" + g.ToString()
        Dim asmbuild As AssemblyBuilder = _
           System.Threading.Thread.GetDomain().DefineDynamicAssembly _
           (asmname, AssemblyBuilderAccess.Run)
        
        ' Add a dynamic module that contains one type that has one method that
        ' has no arguments.
        Dim modbuild As ModuleBuilder = asmbuild.DefineDynamicModule("test")
        Dim tb As TypeBuilder = modbuild.DefineType("name of the Type")
        Dim somemethod As MethodBuilder = _
           tb.DefineMethod("My method Name", _
           MethodAttributes.Public Or(MethodAttributes.Static), _
           GetType(Integer), New Type() {})
        ' Define the body of the method to return 0.
        Dim ilg As ILGenerator = somemethod.GetILGenerator()
        ilg.Emit(OpCodes.Ldc_I4_0)
        ilg.Emit(OpCodes.Ret)
        
        ' Complete the type and verify that it returns 0.
        Dim tbBaked As Type = tb.CreateType()
        Dim res1 As Integer = _
           CInt(tbBaked.GetMethod("My method Name").Invoke _
           (Nothing, New Object() {}))
        If res1 <> 0 Then
            Console.WriteLine("Err_001a, should have returned 0")
        Else
            Console.WriteLine("Original method returned 0")
        End If
        
        ' Define a new method body that will return a 1 instead.
        Dim methodBytes As Byte() = _
        {&H3, &H30, &HA, &H0, &H2, &H0, &H0, &H0, &H0, &H0, &H0, &H0, &H17, &H2A}
        '&H2     code size
        '&H17    ldc_i4_1
        '&H2A    ret
        
        ' Get the token for the method whose body you are replacing.
        Dim somemethodToken As MethodToken = somemethod.GetToken()
        
        ' Get the pointer to the method body.
        Dim hmem As GCHandle = _
           GCHandle.Alloc(CType(methodBytes, Object), GCHandleType.Pinned)
        Dim addr As IntPtr = hmem.AddrOfPinnedObject()
        Dim cbSize As Integer = methodBytes.Length
        
        ' Swap the old method body with the new body.
        MethodRental.SwapMethodBody(tbBaked, somemethodToken.Token, addr, _
           cbSize, MethodRental.JitImmediate)
        
        ' Verify that the modified method returns 1.
        Dim res2 As Integer = _
           CInt(tbBaked.GetMethod("My method Name").Invoke _
           (Nothing, New Object() {}))
        If res2 <> 1 Then
            Console.WriteLine("Err_001b, should have returned 1")
        Else
            Console.WriteLine("Swapped method body returned 1")
        End If
    End Sub
End Class

注釈

このメソッドを使用してグローバル メソッドの本体を入れ替えることはできません。

メソッドを呼び出すことができるのは、メソッドの本体がスワップされる型を含む動的モジュールを作成したクライアントだけです。

適用対象