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ILGenerator.EmitCall(OpCode, MethodInfo, Type[]) Метод

Определение

Помещает инструкцию call или callvirt в поток языка MSIL для вызова метода varargs.

public:
 virtual void EmitCall(System::Reflection::Emit::OpCode opcode, System::Reflection::MethodInfo ^ methodInfo, cli::array <Type ^> ^ optionalParameterTypes);
public:
 abstract void EmitCall(System::Reflection::Emit::OpCode opcode, System::Reflection::MethodInfo ^ methodInfo, cli::array <Type ^> ^ optionalParameterTypes);
public:
 void EmitCall(System::Reflection::Emit::OpCode opcode, System::Reflection::MethodInfo ^ methodInfo, cli::array <Type ^> ^ optionalParameterTypes);
public virtual void EmitCall (System.Reflection.Emit.OpCode opcode, System.Reflection.MethodInfo methodInfo, Type[]? optionalParameterTypes);
public abstract void EmitCall (System.Reflection.Emit.OpCode opcode, System.Reflection.MethodInfo methodInfo, Type[]? optionalParameterTypes);
public virtual void EmitCall (System.Reflection.Emit.OpCode opcode, System.Reflection.MethodInfo methodInfo, Type[] optionalParameterTypes);
public void EmitCall (System.Reflection.Emit.OpCode opcode, System.Reflection.MethodInfo methodInfo, Type[] optionalParameterTypes);
abstract member EmitCall : System.Reflection.Emit.OpCode * System.Reflection.MethodInfo * Type[] -> unit
override this.EmitCall : System.Reflection.Emit.OpCode * System.Reflection.MethodInfo * Type[] -> unit
abstract member EmitCall : System.Reflection.Emit.OpCode * System.Reflection.MethodInfo * Type[] -> unit
member this.EmitCall : System.Reflection.Emit.OpCode * System.Reflection.MethodInfo * Type[] -> unit
Public Overridable Sub EmitCall (opcode As OpCode, methodInfo As MethodInfo, optionalParameterTypes As Type())
Public MustOverride Sub EmitCall (opcode As OpCode, methodInfo As MethodInfo, optionalParameterTypes As Type())
Public Sub EmitCall (opcode As OpCode, methodInfo As MethodInfo, optionalParameterTypes As Type())

Параметры

opcode
OpCode

Инструкция языка MSIL, которую следует включить в поток. Должно быть Call, Callvirt или Newobj.

methodInfo
MethodInfo

Метод varargs, который следует вызывать.

optionalParameterTypes
Type[]

Типы необязательных аргументов, если используется метод varargs. В противном случае указывается значение null.

Исключения

Параметр opcode не задает вызов метода.

methodInfo имеет значение null.

Соглашение о вызовах для метода отличается от varargs. Однако при этом указываются типы необязательных параметров. Это исключение возникает в .NET Framework версии 1.0 и 1.1. В последующих версиях исключение не возникает.

Примеры

В следующем примере кода создаются два метода: varargs метод и метод, вызывающий varargs метод . Метод EmitCall используется для вызова varargs метода .

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

void main() 
{
    String^ name = "InMemory";

    AssemblyBuilder^ asmBldr = 
       AppDomain::CurrentDomain->DefineDynamicAssembly(gcnew AssemblyName(name), 
          AssemblyBuilderAccess::Run);
    ModuleBuilder^ modBldr = asmBldr->DefineDynamicModule(name); 

    TypeBuilder^ tb = modBldr->DefineType("DemoVararg");

    // Create a vararg method with no return value and one 
    // string argument. (The string argument type is the only
    // element of an array of Type objects.)
    //
    MethodBuilder^ mb1 = tb->DefineMethod("VarargMethod",
        MethodAttributes::Public | MethodAttributes::Static,
        CallingConventions::VarArgs,
        nullptr, 
        gcnew array<Type^> { String::typeid });

    ILGenerator^ il1 = mb1->GetILGenerator();

    LocalBuilder^ locAi = il1->DeclareLocal(ArgIterator::typeid);
    LocalBuilder^ locNext = il1->DeclareLocal(bool::typeid);

    Label labelCheckCondition = il1->DefineLabel();
    Label labelNext = il1->DefineLabel();

    // Load the fixed argument and print it.
    il1->Emit(OpCodes::Ldarg_0);
    il1->Emit(OpCodes::Call, Console::typeid->GetMethod("Write", 
         gcnew array<Type^> { String::typeid }));

    // Load the address of the local variable represented by
    // locAi, which will hold the ArgIterator.
    il1->Emit(OpCodes::Ldloca_S, locAi);

    // Load the address of the argument list, and call the 
    // ArgIterator constructor that takes an array of runtime
    // argument handles. 
    il1->Emit(OpCodes::Arglist);
    il1->Emit(OpCodes::Call, ArgIterator::typeid->GetConstructor(
         gcnew array<Type^> { RuntimeArgumentHandle::typeid }));

    // Enter the loop at the point where the remaining argument
    // count is tested.
    il1->Emit(OpCodes::Br_S, labelCheckCondition);

    // At the top of the loop, call GetNextArg to get the next 
    // argument from the ArgIterator. Convert the typed reference
    // to an object reference and write the object to the console.
    il1->MarkLabel(labelNext);
    il1->Emit(OpCodes::Ldloca_S, locAi);
    il1->Emit(OpCodes::Call, ArgIterator::typeid->GetMethod("GetNextArg", Type::EmptyTypes));
    il1->Emit(OpCodes::Call, TypedReference::typeid->GetMethod("ToObject"));
    il1->Emit(OpCodes::Call, Console::typeid->GetMethod("Write", 
         gcnew array<Type^> { Object::typeid }));

    il1->MarkLabel(labelCheckCondition);
    il1->Emit(OpCodes::Ldloca_S, locAi);
    il1->Emit(OpCodes::Call, ArgIterator::typeid->GetMethod("GetRemainingCount"));

    // If the remaining count is greater than zero, go to
    // the top of the loop.
    il1->Emit(OpCodes::Ldc_I4_0);
    il1->Emit(OpCodes::Cgt);
    il1->Emit(OpCodes::Stloc_1);
    il1->Emit(OpCodes::Ldloc_1);
    il1->Emit(OpCodes::Brtrue_S, labelNext);

    il1->Emit(OpCodes::Ret);

    // Create a method that contains a call to the vararg 
    // method.
    MethodBuilder^ mb2 = tb->DefineMethod("CallVarargMethod",
        MethodAttributes::Public | MethodAttributes::Static,
        CallingConventions::Standard,
        nullptr, Type::EmptyTypes);

    ILGenerator^ il2 = mb2->GetILGenerator();

    // Push arguments on the stack: one for the fixed string
    // parameter, and two for the list.
    il2->Emit(OpCodes::Ldstr, "Hello ");
    il2->Emit(OpCodes::Ldstr, "world ");
    il2->Emit(OpCodes::Ldc_I4, 2006);

    // Call the vararg method, specifying the types of the 
    // arguments in the list.
    il2->EmitCall(OpCodes::Call, mb1, 
        gcnew array<Type^> { String::typeid, int::typeid });

    il2->Emit(OpCodes::Ret);

    Type^ type = tb->CreateType();
    type->GetMethod("CallVarargMethod")->Invoke(nullptr, nullptr);
}

/* This code example produces the following output:

Hello world 2006
 */
using System;
using System.Reflection;
using System.Reflection.Emit;

class Example
{
    static void Main()
    {
        string name = "InMemory";

        AssemblyBuilder asmBldr =
           AppDomain.CurrentDomain.DefineDynamicAssembly(new AssemblyName(name),
              AssemblyBuilderAccess.Run);
        ModuleBuilder modBldr = asmBldr.DefineDynamicModule(name);

        TypeBuilder tb = modBldr.DefineType("DemoVararg");

        // Create a vararg method with no return value and one
        // string argument. (The string argument type is the only
        // element of an array of Type objects.)
        //
        MethodBuilder mb1 = tb.DefineMethod("VarargMethod",
            MethodAttributes.Public | MethodAttributes.Static,
            CallingConventions.VarArgs,
            null,
            new Type[] { typeof(string) });

        ILGenerator il1 = mb1.GetILGenerator();

        LocalBuilder locAi = il1.DeclareLocal(typeof(ArgIterator));
        LocalBuilder locNext = il1.DeclareLocal(typeof(bool));

        Label labelCheckCondition = il1.DefineLabel();
        Label labelNext = il1.DefineLabel();

        // Load the fixed argument and print it.
        il1.Emit(OpCodes.Ldarg_0);
        il1.Emit(OpCodes.Call, typeof(Console).GetMethod("Write", new Type[] { typeof(string) }));

        // Load the address of the local variable represented by
        // locAi, which will hold the ArgIterator.
        il1.Emit(OpCodes.Ldloca_S, locAi);

        // Load the address of the argument list, and call the
        // ArgIterator constructor that takes an array of runtime
        // argument handles.
        il1.Emit(OpCodes.Arglist);
        il1.Emit(OpCodes.Call, typeof(ArgIterator).GetConstructor(new Type[] { typeof(RuntimeArgumentHandle) }));

        // Enter the loop at the point where the remaining argument
        // count is tested.
        il1.Emit(OpCodes.Br_S, labelCheckCondition);

        // At the top of the loop, call GetNextArg to get the next
        // argument from the ArgIterator. Convert the typed reference
        // to an object reference and write the object to the console.
        il1.MarkLabel(labelNext);
        il1.Emit(OpCodes.Ldloca_S, locAi);
        il1.Emit(OpCodes.Call, typeof(ArgIterator).GetMethod("GetNextArg", Type.EmptyTypes));
        il1.Emit(OpCodes.Call, typeof(TypedReference).GetMethod("ToObject"));
        il1.Emit(OpCodes.Call, typeof(Console).GetMethod("Write", new Type[] { typeof(object) }));

        il1.MarkLabel(labelCheckCondition);
        il1.Emit(OpCodes.Ldloca_S, locAi);
        il1.Emit(OpCodes.Call, typeof(ArgIterator).GetMethod("GetRemainingCount"));

        // If the remaining count is greater than zero, go to
        // the top of the loop.
        il1.Emit(OpCodes.Ldc_I4_0);
        il1.Emit(OpCodes.Cgt);
        il1.Emit(OpCodes.Stloc_1);
        il1.Emit(OpCodes.Ldloc_1);
        il1.Emit(OpCodes.Brtrue_S, labelNext);

        il1.Emit(OpCodes.Ret);

        // Create a method that contains a call to the vararg
        // method.
        MethodBuilder mb2 = tb.DefineMethod("CallVarargMethod",
            MethodAttributes.Public | MethodAttributes.Static,
            CallingConventions.Standard,
            typeof(void), Type.EmptyTypes);
        ILGenerator il2 = mb2.GetILGenerator();

        // Push arguments on the stack: one for the fixed string
        // parameter, and two for the list.
        il2.Emit(OpCodes.Ldstr, "Hello ");
        il2.Emit(OpCodes.Ldstr, "world ");
        il2.Emit(OpCodes.Ldc_I4, 2006);

        // Call the vararg method, specifying the types of the
        // arguments in the list.
        il2.EmitCall(OpCodes.Call, mb1, new Type[] { typeof(string), typeof(int) });

        il2.Emit(OpCodes.Ret);

        Type type = tb.CreateType();
        type.GetMethod("CallVarargMethod").Invoke(null, null);
    }
}

/* This code example produces the following output:

Hello world 2006
 */
Imports System.Reflection
Imports System.Reflection.Emit

Class Example
    
    Shared Sub Main() 

        Dim name As String = "InMemory"
        
        Dim asmBldr As AssemblyBuilder = AppDomain.CurrentDomain.DefineDynamicAssembly( _
            New AssemblyName(name), AssemblyBuilderAccess.Run)
        Dim modBldr As ModuleBuilder = asmBldr.DefineDynamicModule(name)
        
        Dim tb As TypeBuilder = modBldr.DefineType("DemoVararg")
        
        ' Create a vararg method with no return value and one 
        ' string argument. (The string argument type is the only
        ' element of an array of Type objects.)
        '
        Dim mb1 As MethodBuilder = tb.DefineMethod("VarargMethod", _
            MethodAttributes.Public Or MethodAttributes.Static, _
            CallingConventions.VarArgs, _
            Nothing, _
            New Type() {GetType(String)})
        
        Dim il1 As ILGenerator = mb1.GetILGenerator()
        
        Dim locAi As LocalBuilder = il1.DeclareLocal(GetType(ArgIterator))
        Dim locNext As LocalBuilder = il1.DeclareLocal(GetType(Boolean))
        
        Dim labelCheckCondition As Label = il1.DefineLabel()
        Dim labelNext As Label = il1.DefineLabel()
        
        ' Load the fixed argument and print it.
        il1.Emit(OpCodes.Ldarg_0)
        il1.Emit(OpCodes.Call, GetType(Console).GetMethod("Write", _
            New Type() {GetType(String)}))
        
        ' Load the address of the local variable represented by
        ' locAi, which will hold the ArgIterator.
        il1.Emit(OpCodes.Ldloca_S, locAi)
        
        ' Load the address of the argument list, and call the 
        ' ArgIterator constructor that takes an array of runtime
        ' argument handles. 
        il1.Emit(OpCodes.Arglist)
        il1.Emit(OpCodes.Call, GetType(ArgIterator).GetConstructor( _
            New Type() {GetType(RuntimeArgumentHandle)}))
        
        ' Enter the loop at the point where the remaining argument
        ' count is tested.
        il1.Emit(OpCodes.Br_S, labelCheckCondition)
        
        ' At the top of the loop, call GetNextArg to get the next 
        ' argument from the ArgIterator. Convert the typed reference
        ' to an object reference and write the object to the console.
        il1.MarkLabel(labelNext)
        il1.Emit(OpCodes.Ldloca_S, locAi)
        il1.Emit(OpCodes.Call, _
            GetType(ArgIterator).GetMethod("GetNextArg", Type.EmptyTypes))
        il1.Emit(OpCodes.Call, GetType(TypedReference).GetMethod("ToObject"))
        il1.Emit(OpCodes.Call, _
            GetType(Console).GetMethod("Write", New Type() {GetType(Object)}))
        
        il1.MarkLabel(labelCheckCondition)
        il1.Emit(OpCodes.Ldloca_S, locAi)
        il1.Emit(OpCodes.Call, _
            GetType(ArgIterator).GetMethod("GetRemainingCount"))
        
        ' If the remaining count is greater than zero, go to
        ' the top of the loop.
        il1.Emit(OpCodes.Ldc_I4_0)
        il1.Emit(OpCodes.Cgt)
        il1.Emit(OpCodes.Stloc_1)
        il1.Emit(OpCodes.Ldloc_1)
        il1.Emit(OpCodes.Brtrue_S, labelNext)
        
        il1.Emit(OpCodes.Ret)
        
        ' Create a method that contains a call to the vararg 
        ' method.
        Dim mb2 As MethodBuilder = tb.DefineMethod("CallVarargMethod", _
            MethodAttributes.Public Or MethodAttributes.Static, _
            CallingConventions.Standard, _
            Nothing, _
            Type.EmptyTypes)

        Dim il2 As ILGenerator = mb2.GetILGenerator()
        
        ' Push arguments on the stack: one for the fixed string
        ' parameter, and two for the list.
        il2.Emit(OpCodes.Ldstr, "Hello ")
        il2.Emit(OpCodes.Ldstr, "world ")
        il2.Emit(OpCodes.Ldc_I4, 2006)
        
        ' Call the vararg method, specifying the types of the 
        ' arguments in the list.
        il2.EmitCall(OpCodes.Call, mb1, _
            New Type() {GetType(String), GetType(Integer)})
        
        il2.Emit(OpCodes.Ret)
        
        Dim myType As Type = tb.CreateType()
        myType.GetMethod("CallVarargMethod").Invoke(Nothing, Nothing)
    
    End Sub 
End Class 

' This code example produces the following output:
'
'Hello world 2006
'

Комментарии

Метод EmitCall используется для выдачи вызовов методов, varargs так как не существует перегрузки Emit метода, задающего типы параметров аргументов переменной.

Чтобы вызывать методы, которые не используют соглашение о вызовах VarArgs , используйте перегрузку Emit(OpCode, MethodInfo) метода .

Метод EmitCall не создает исключение, если для метода, не равного varargs, указаны необязательные типы параметров. InvalidProgramException вызывается при выполнении вызова.

Применяется к